Switch to Synthetic Oil?

[mudpuddle]

Ok, I'v heard the stories about the switch to synthetic motor oils causing leaks in older vehicles. I have an '01 with 90K and want to switch to synthetic, but aren't too crazy about the prospect of discovering a leak. I don't presently have ANY leaks. What is everyone's experience with switching over on later model XJs?

[RichP]

Ok, I'v heard the stories about the switch to synthetic motor oils causing leaks in older vehicles. I have an '01 with 90K and want to switch to synthetic, but aren't too crazy about the prospect of discovering a leak. I don't presently have ANY leaks. What is everyone's experience with switching over on later model XJs?

Should not be an issue, make the change BUT keep an eye on the dipstick, the syn will start cleaning the engine out and the oil will get dirty faster, when you can't read the dipstick anymore change the filter, once the filter plugs the bypass kicks in and cycles unfiltered oil which you don't want.

[ponyracer1]

I have an 01 and made the switch with no probs. Going to do the tranny and diffs next.

I have noticed the oil turning black fast though, only been in about 1k and it's just above being black.

[Jay Welch]

I love the stuff and use Mobil 1 in everything I can.....BUT, my 2000 XJ just didn't like the stuff. I bought it at 116K. It was very well maintained and the inside of the engine is very clean. Right after I changed the oil it started to drip from the rear main seal. I drained out 3 quarts of the synthetic and added 3 quarts of dino oil. The oil leak stopped for the most part. Next change will receive 2 quarts synthetic and 4 quarts dino.....if it still weeps it will go back to all dino. If I keep the XJ it will probably get a new rear main seal.

I'd at least try it. Do a search on "synthetic". There's a lot of posts on it.

Good luck,
Jay in MA

[RichP]

I have an 01 and made the switch with no probs. Going to do the tranny and diffs next.

I have noticed the oil turning black fast though, only been in about 1k and it's just above being black.

If you have the auto tranny I'd go cautious, there has been some mixed results when going syn on the AW. The results have varied between 'good' to 'destroyed' it. With syn oil generally the worst thing that can happen is leaks, tranny can have other problems.

[MogifiedXJ]

If you have the auto tranny I'd go cautious, there has been some mixed results when going syn on the AW. The results have varied between 'good' to 'destroyed' it. With syn oil generally the worst thing that can happen is leaks, tranny can have other problems.

x2

Do not put syn in your transmission unless it was made for it. Period. Once you start using syn in your engine I've always heard that you're not supposed to go back to regular oil either. I run mobil 1 in my yota and love the stuff...I still change it every 3000 miles and it's the same color as the day I poured it in. My father runs shaffer oil in his work trucks and likes it. It's a parrafin wax based oil, other than that I don't know much about it though other than the fact it was designed for use in the big rig industry.

[langer1]

...I still change it every 3000 miles and it's the same color as the day I poured it in.

Thats not good, the color change with any oil is dirt that it cleaned and gathered from the engine.

Non-detergent motor oil also is also clear between oil changes.

[Jay Welch]

These might be older links but a lot of good reading if want to gain more knowledge.

http://www.boss302.com/oil.htm
http://www.getahelmet.com/jeeps/tech/syntheticoil/
http://neptune.spacebears.com/cars/stories/oil-life.html
http://www.mr2.com/TEXT/synth_oil.txt
http://yotarepair.com/Automotive_News.html
http://www.amsoil.com/articlespr/2005/pr_extended_drain.aspx
http://www.amsoil.com/
http://www.mobil1.com/index.jsp
http://www.exxonmobil.com/Corporate/Newsroom/Newsreleases/xom_nr_250105_02.asp
http://www.mobiloil.com/USA-English/MotorOil/Oils/Mobil_1_Extended_Performance.aspx

[techno1154]

I use synthetic; Amsoil in everything including the AW4 for about 75,000 miles. Bought the XJ at 135,00 and switched at my first oil change. My only pproblem was oil leaks from the 4.0 for some 20,00 miles then they all went away except the front of the engine. I have no problem whatsoever with anything. I will not go back to Dino juice.

[PolishX]

what about a blend . like the Quaker state stuff

[Jay Welch]

I thiink you would be better off making your own blend.

From the article at http://www.boss302.com/oil.htm

"Let's see...blended oils.

The oil companies found out that by adding a small amount of synthetic base stock to conventional 'dino' stock, they were able to significantly increase its cold and hot temperature performance. It approaches full-synthetic performance, but is still a ways away. (Blended oils are almost a definite with GF-4/5 oils). They are significantly better than regular 'dino'. However, there are still the trace elements in the 'dino' portion of the oil, and that is what contributes to sludge formation. For that reason, I do not use blended oils. Blended oils use anywhere from 2% to 5% synthetic base, depending on viscosity and brand. None are higher than 5%. (Most erroneously assume it is 50/50). This is a BIG moneymaker for the oil companies."

[exjay33]

Mobil one is not a true synthetic oil it is dino based oil , there are only a couple true syn. on the market Amsoil Royal Purple and the jury is still out on Red Line . And syntheic do not cause leaks and you can mix oils but not recommended . Also changing a trans to syn. oil will not cause it to go out you have to make sure you put the right oil in , also the worst thing you can do to a trans that has never been cared for is to start caring late in its life . You will pay for a good oil but you also increase change times it figures the same in the end Amsoil offers an oil you can change once a year or 25000 miles just change filter at 4000 or 5000 . If you where to put a good filter system on you wouldn't really have to change just filters and send a sample every 7500 miles don't change till they tell you too .

[RichP]

what about a blend . like the Quaker state stuff

I've threatned to shoot anybody who brings quacker state or pennz on the property.
You could mix your own in a 50/50 mix, I'd stay brand same thiough, like mobil dino and mobil-1 or castrol and castrol syntec. More than a couple of times I've had to add a quart of normal oil to my Mobil-1.

[Jay Welch]

http://www.mobiloil.com/USA-English/MotorOil/Oils/Mobil_1_FAQs.aspx#FAQs1

[Jay Welch]

I agree, I won't use either.

...........I've threatned to shoot anybody who brings quacker state or pennz on the property.

[Ben H]

I love the stuff and use Mobil 1 in everything I can.....BUT, my 2000 XJ just didn't like the stuff. I bought it at 116K. It was very well maintained and the inside of the engine is very clean. Right after I changed the oil it started to drip from the rear main seal. I drained out 3 quarts of the synthetic and added 3 quarts of dino oil. The oil leak stopped for the most part. Next change will receive 2 quarts synthetic and 4 quarts dino.....if it still weeps it will go back to all dino. If I keep the XJ it will probably get a new rear main seal.

I'd at least try it. Do a search on "synthetic". There's a lot of posts on it.

Good luck,
Jay in MA


Same thing happened in my 00'. Made the switch to synthetic, and a day later my rear main seal started leaking. A month later, most of my gaskets started seeping. Went back to old fashioned 76 oil and gaskets quit seeping and rear main seal quit leaking as much.

[RCman]

Well, I can't comment on the whole leak issue as before I grenaded my old engine last November I used Mobil 5000 (was Mobil 'Drive Clean' then) 10W30.

After the build-up on my new engine and the increased tolerances for longer life (I play hard :) ) I've been using Mobil 1 15W50 (after proper break-in of course). However, my local NAPA had a sale last time I did and oil change on Royal Purple 20W50, so I figured 'why not'. I tell you, I won't be going back to Mobil 1. There may be a big cost difference from Royal Purple to well, anything else, but my heavy lift tick (performance cam) has greatly reduced and it seems to idle somewhat smoother. I figure if I spent that kinda cash building up a nice engine, why not treat it to the good Royal Purple and a K&N Filter? On an older engine, I'd probably run just regular Dino Oil...

[Jay Welch]

That's good to know. I didn't know NAPA sold the Royal Purple product.....good stuff. Do you know if the entire product line is available through them?

.......... However, my local NAPA had a sale last time I did and oil change on Royal Purple 20W50, so I figured 'why not'.

[langer1]

A few years ago almost every fleet owner in the US jumped on the syn band wagon.
The promise was less maintenance and longer life, and in many cases free oil for their endorsement.
These days only the ones that get it free still use it.

The internal combustion engine running on Gas or Diesel is a very dirty piece of equipment.

Filtration can't remove the chemicals that cause the most problems so you still need to do regular oil changes at 3000 or 5000 miles, even for warranty coverage so it don't make any difference if you use $6.00 a quart syn or quality Dino as long as you change it.

Now having said that using syn in other parts of the vehicle does make sense.

[RCman]

That's good to know. I didn't know NAPA sold the Royal Purple product.....good stuff. Do you know if the entire product line is available through them?

Just called my local NAPA to ask and they said they could get anything in the product line (inculding apparel and stickers) with 2 days notice. However, the stuff ain't cheap so it might be better to get it online and pay shipping depending on what your lookng for.

Filtration can't remove the chemicals that cause the most problems so you still need to do regular oil changes at 3000 or 5000 miles, even for warranty coverage so it don't make any difference if you use $6.00 a quart syn or quality Dino as long as you change it.

Agree 100%. I don't think I'd ever get myself to change my oil at anything more than 3000-5000 even when I pay top dollar for it. However a good filter goes along way, but thats another topic!

[Big Red]

How about 5 quarts of Dino 10W30 oil and 1 quart of Lucas Stabalizer? That's what I did and like how my oil pressure is staying up even at idle in my 98' 5 speed with 131K miles. Before the oil change the pressure would drop to 15 or so, the manual says 12 psi is o.k., but with the Lucas added I can keep about 30 psi most of the time until the Jeep warms up and after 1/2 hour the lowest is gets is like 20 psi in neutral/idle.

[xj9687]

maybe you should start to run a blend for a oil change or two then switch it to full syn. thats what i did in my 96 i used blend for about a year from about 137-163ish and then just switched to full syn the last oil change with 164 on the clock. i noticed before that the bottom of my filter and oil pan and even the trans pan was always wet with oil before but now i got up under the other day and it was looking all dryed up and the bottom of the K&N filter was dry thats another thing i decided to spend the extra money on too. so id say try it. another thing that it did was now my oil pressure is always at 40 or so at idle and its always around 65-70 while im driving and its still there after about 3300 miles.

[DenLip]

The internal combustion engine running on Gas or Diesel is a very dirty piece of equipment.

Depends a LOT on the engine. The Jeep, yes... the oil gets black pretty quickly. But I still "trust" the better formulation, and better lubricating qualities, of the synthetic to allow me to stretch the interval... within reason.

My old Dodge Stratus... and the new Honda... both have oil that was still "honey-like" at 3k miles. On the Stratus, I'd gradually pushed the dino-oil change interval out to 5k, where it was still only a syrup-like brown. If the engine burns clean enough to not produce the ugly byproducts, they won't get into the oil...

In the Jeep's case, rather than changing dino juice every 3k, I run Mobil 1 for 6k, with a midterm filter change. With the current high cost of dino juice (close to $2/quart!), the $4/qt Mobil 1 costs me little more than regular oil did... PLUS, I use (and have to dispose of...) half as much oil.

Den

[bewilderedbeast]

This may not matter, but I've seen numerous Used Oil Analyses on the 4.0 and Mobil 1 10W30 has shown elevated iron wear rates.
I know many say "Well, I've run Mobil 1 10W30 for XXX,XXX miles and no problem."
But without doing a UOA, you don't know how well your drivetrain is being protected, or how many more XXX,XXX miles you could get with an oil that has better metal wear rates.
If anybody wants a look, I have loads of data on this engine, using various brands, and viscosities.

[Gator4x]

Anyone noticed the manual actually says 7500 miles between oil changes for normal driving?

[Big Red]

This may not matter, but I've seen numerous Used Oil Analyses on the 4.0 and Mobil 1 10W30 has shown elevated iron wear rates.
I know many say "Well, I've run Mobil 1 10W30 for XXX,XXX miles and no problem."
But without doing a UOA, you don't know how well your drivetrain is being protected, or how many more XXX,XXX miles you could get with an oil that has better metal wear rates.
If anybody wants a look, I have loads of data on this engine, using various brands, and viscosities.

Please post what you have on the 4.0L and different oil, we all want to know about that. Kelley (5-90) would also want this for his research he has done on Jeeps I'm sure.

thanks,

Troy

[90xj06]

speaking of synthetic. my jeep has run probably dino oil in it sense new. well today my breather hose fell off. and i was appealed at the amount of sludge in the valve area. so im going to take that valve cover off and clean it up a bit.

[bewilderedbeast]

Please post what you have on the 4.0L and different oil, we all want to know about that. Kelley (5-90) would also want this for his research he has done on Jeeps I'm sure.

thanks,

Troy

What I have is on an Excel spredasheet, I'd be happy to send it to whoever wants, or I can summmarize and hit the hight spots in a post, whichever is better.

[Root Moose]

What I have is on an Excel spredasheet, I'd be happy to send it to whoever wants, or I can summmarize and hit the hight spots in a post, whichever is better.
If you want, PM me with an email address to make contact. I will attempt to "webify" the spreadsheet and make it publicly available.

[EricT]

I've threatned to shoot anybody who brings quacker state or pennz on the property.



That and Fram

[chelms27]

went to quaker state synthetic about 1500K ago, now I have leaks, and lower oil pressure at idle. It hasnt turned black, and it seems like it is working ok, but wouldnt use it again, back to Valvoline for me!

[RyanM]

Royal Purple 10w-40 summer, 10 30 winter. K&N or Wix(napa) filter. been using it for over a year now. i could definately tell it was cleaning the dino residue as i changed it every 3K.
no changes in pressure tho. its always stayed right over 40 at idle and about 50 under normal driving.

i now run it about 6K(calls for 10-12K with a mid filter change i think). i
it has held up to my 5000RPM engine revs so far ;)

edit: i just read the subject line. whould you switch? if you want, i dunno :)

[EricT]

I thought I read somewhere that RP puts moly in their oil.

[RyanM]

i have read this as wel but also thought it was only in their racing oils. Moly only causes adverse affects when the oil is used in extreme extended situations. anybody else have any comments on it.


edit. I sent them an EMAIL, i'll post what they have to say when i get it. might be a good reason to switch to Amsoil.

[DenLip]

Anyone noticed the manual actually says 7500 miles between oil changes for normal driving?

Yes, but... their definition of "normal" specifically excludes:

- idling
- lots of highway
- lots of short trips
- cold-weather operation
- hot-weather operation
- towing

Almost nobody qualifies as "normal". My dealers (who, of course, are trying to sell lots of oil changes!) have always said that in this area (western PA) EVERYBODY qualifies as "severe duty", and must follow the severe schedule for maintenance.

(The unstated penalty is loss of warranty coverage... but I've never had one who was THAT BOLD about it).

Den

[langer1]

This may not matter, but I've seen numerous Used Oil Analyses on the 4.0 and Mobil 1 10W30 has shown elevated iron wear rates.
I know many say "Well, I've run Mobil 1 10W30 for XXX,XXX miles and no problem."
But without doing a UOA, you don't know how well your drivetrain is being protected, or how many more XXX,XXX miles you could get with an oil that has better metal wear rates.
If anybody wants a look, I have loads of data on this engine, using various brands, and viscosities.

I have seen simular UOA tests where I work, and Mobil oil did our tests every 3 months.

[Big Red]

That and Fram

Why do you hate their marketing campain, or is their oil really that inferior???

[RyanM]

I thought I read somewhere that RP puts moly in their oil.
For you EricT and anybody else who gives a fawk, this is my response from RP.
-------------------------------------------------------------------------
From : Patrick Burris <patrickb@royalpurple.com>
Reply-To : <patrickb@royalpurple.com>
Sent : Tuesday, September 12, 2006 11:36 AM
To : "'ryan marshall'" <skyjackedxj1996@hotmail.com>
Subject : RE: Auto Oil Question, please respond.




Ryan
As usual the information you got from Amsoil is not correct. Royal
Purple does not use MOLY.


Thanks
Patrick Burris
Motorsports Marketing Coordinator
One Royal Purple Lane
Porter TX. 77365
Office 281-354-8600 Ext 241
Fax 281-354-7335
Cell 713-705-9201

-----Original Message-----
From: ryan marshall [mailto:skyjackedxj1996@hotmail.com]
Sent: Tuesday, September 12, 2006 1:55 AM
To: rpautotech@royalpurple.com
Subject: Auto Oil Question, please respond.

I have been using your automobile oil in my Jeep 4.0 for about a year. I
was recently told you guys were making it wth MOLY. Amsoil claims their oil
causes less wear on metals because they don't use MOLY. so what is the
deal? am i doing more harm on my motor than i think? am i clongging lines
and filters prematurely because of the MOLY addative?

thanks
Ryan Marshall
VA

[bewilderedbeast]

Moly doesn't clog anything, and the new SM oils with lots of moly are showing good wear protection.

[RyanM]

http://www.performancemotoroil.com/Royal_Purple_info.html

[EricT]

Why do you hate their marketing campain, or is their oil really that inferior???

from seeing what it has done to engines that I have taken apart in the past, my dad use to swear by it till we tore into his 914 engine for a rebuild, switched to castrol and have not see the same problems

I used to use mobil 1 in all my vehicles. One time I did an experiment with amsoil in my track car, with mobil 1 and a 1 qt larger oil pan, I was seeing oil temps peaking at 267 degrees. I switched to Amsoil on even a hotter day at the track and my temps were back down to 237 peak. The amsoil disipated the heat better, so I have been a believer since.

[GhostDakota]

I'm running Mobil 1 Synthetic on my '91... the engine is a '93 with roughly 59k miles on it. I was leaking very slightly from my rear main seal, and I am still leaking slightly from it. Nothing more than before. I changed the oil about 5k miles ago and I just added one quart to it. No big deal. My old YJ used to suck up 1 quart a WEEK on regular oil!

Also, what do you all think of Amsoil/Royal Purple?

Edit: I see the thoughts on Amsoil lol.. From what I have heard, it's the same thing about it being a GREAT motor oil.

[GhostDakota]

This may not matter, but I've seen numerous Used Oil Analyses on the 4.0 and Mobil 1 10W30 has shown elevated iron wear rates.
I know many say "Well, I've run Mobil 1 10W30 for XXX,XXX miles and no problem."
But without doing a UOA, you don't know how well your drivetrain is being protected, or how many more XXX,XXX miles you could get with an oil that has better metal wear rates.
If anybody wants a look, I have loads of data on this engine, using various brands, and viscosities.

I would love to see it! Do you have data from Mobil 1 Synthetic, Royal Purple and Amsoil? Thank you!

[bewilderedbeast]

I would love to see it! Do you have data from Mobil 1 Synthetic, Royal Purple and Amsoil? Thank you!
PM me with an email address and I'll send you the file. So far, I have 20 samples, and there is indeed an Amsoil 5W40 thereas well as several Mobil 1. I haven't copied all the UOA's available yet, but this is a start.

[Root Moose]

PM me with an email address and I'll send you the file. So far, I have 20 samples, and there is indeed an Amsoil 5W40 thereas well as several Mobil 1. I haven't copied all the UOA's available yet, but this is a start.
I have the spreadsheet and will post as PDF some time this PM - if the weather holds - satellite is winking out and I have work that needs to be done when it is "up".

Hold that thought...

[Root Moose]

Ok, dish is green for longer than 30 seconds... But the rain is coming down harder...

Here's the PDF:

Oil_comp_Analysis.xls.pdf (http://moose.ca/content/PDF/Oil_comp_Analysis.xls.pdf)

[GhostDakota]

Ok, dish is green for longer than 30 seconds... But the rain is coming down harder...

Here's the PDF:

Oil_comp_Analysis.xls.pdf (http://moose.ca/content/PDF/Oil_comp_Analysis.xls.pdf)

Thanks much! Is this the same thing that was stated before? :)

[Big Red]

Thanks Root Moose for the data. What conclusions can be made from them? What's the best oil? Can a Dino oil compare to a synthetic.

[GhostDakota]

The charts are kind of confusing to me? I see the Viscosity, etc., but not sure which numbers are which oils, what the Fe wear means, etc. What order are they in from best to worst?

[Comanchedude]

[QUOTE=exjay33]Mobil one is not a true synthetic oil it is dino based oil ,

I would like you to prove that statment, as it is WRONG

[bewilderedbeast]

It is indeed wrong. Mobil 1 is a Group IV synthetic.
Group III is a severely hydrocracked dino oil.(Rotella T-Syn, Castrol Syntec, maybe Pennzoil Platinum).
Doesn't really matter, does it? Aren't results what count?

[ltkaknm]

So in summation is there a concensus on whether going to Synthetic is a good thing? I have a 90 XJ 4.0 L and I have been using the SUV mix with Lucas Oil Stabilizer but I am thinking of switching to Mobil 1. I use the high end Mobil 1 filter and it seems to work well.

I do have some oil leaks and I would be interested to see if switching to synthetics would help or hurt.

Any advice would be appreciated

LTK

[SCW]

I don't think there really is a concensus. this is just a big internet commitee, nothing is ever decided on.

I tried a synthetic blend and ended up changing the rear main, filter O-rings and valve cover gasket before it quit leaking. If your prepared for that possibility, try it out.

[bewilderedbeast]

I think that if you're changing at 3000-5000 miles, it's a waste of money to buy a synthetic, since for short intervals there's not much difference in wear rates.
If something gets "cleaned" by a synthetic oil, or a cleaner like Auto-RX, it's something that shouldn't be there anyway. Just my opinion.

[Big Red]

I think that if you're changing at 3000-5000 miles, it's a waste of money to buy a synthetic, since for short intervals there's not much difference in wear rates.
If something gets "cleaned" by a synthetic oil, or a cleaner like Auto-RX, it's something that shouldn't be there anyway. Just my opinion.

True both those natural oil leak plugger Dino oil residue are nice. Kind of sucks when your Jeep starts leaking like crazy when you go to synthetic.

[bewilderedbeast]

Yep, but if it's been kept fairly clean, it won't.

[EricT]

The charts are kind of confusing to me? I see the Viscosity, etc., but not sure which numbers are which oils, what the Fe wear means, etc. What order are they in from best to worst?


Fe wear is probably the amount of iron in the oil, but like you, I don't know how the numbers are labeled.

[ddeadserious]

I did one oil change with synthetic and it made a massive leak(at least 1qt/day) until about 3 days later where i did another change using non-synthetic 20W50. It still leaks wayyyyy more than before the synthetic switch.

[rescuejeeper]

I started using full synthetic oil in my '95 XJ about 5 years ago. I swear by the stuff, and would never go back to regular oil. I use full synthetic oil in all 3 of my jeeps, it can be expensive but well worth the price.

As far as a leak, I did have one in my '95 but that was a loose valve cover gasket.

[mikeny59]

Full synthetic switchover at 3k miles back in '98, 116k now, engine idles and pulls better than new, I still change oil/filter at frequent intervals, less stress than a motor rebuild in the long run is my philosphy; just cut some financial corners elsewhere to afford it :rattle:

Btw, this includes the aw4, I must be one of those lucky exceptions, even w/3.55's and 31's and pita shifting in and out of od manually all the time, no sign of odd behaviors or slippage, etc...

Includes religious screen changes/cleaning and not stompin' on it.

All Mobil1.

[badron]

Dino has been used by all I know for as long as I can remember. In almost every case the engine has out lasted the rest of the car. If the engine outlast the rest of the car on dino, (to be fare I live in N Ohio and we use lots of salt here) Why would anyone want to spend any more money on Sin oil. You will never receive any payback for the extra cost.
Now for heavy trucks, towing, or any case of were the engine is subject to extreme loads/heat Sin oil may payoff.
But for the most engines used as intended or in the normal manner. Sin oil is a waste of money.
I pull a 43?? LB trailer and when I do you better believe Sin oil is in the oil pan. The rest of the time and in the other XJ dino get the job done at a better price.

[RichP]

Reason one, it's fairly cheap insurance for those of us who keep them till they ain't no good no more. I'm on my second engine on my 98, had over 300,000mi on it when an injector stuck open and took out the #3 cylinder. Replaced with a jasper reman.
Easier winter starts, at -5f it spins as fast on the morning startup as it does the rest of the year which is easier on the battery and the starter.

But I also use mobil-1 and K&N filters too... Mobill-1 in the AX15 and the NP231 too as well as the front diff, rear is running drydene with frictionmodifier for the auburn thats back there..
Actaully all three of our jeeps run the same thing as well as the wifes Oldsmobile. Its nice all the jeeps take the same filter and such, easier shopping....

[mikeny59]

Rich, what is drydene? I still have a trutrac and auburn and 4.10's that I never got around to installing, including four bottles of gmc friction modifier that's like four years old (does the stuff have a shelf life?!?).

[badron]

====================================
Easier winter starts, at -5f it spins as fast on the morning startup as it does the rest of the year which is easier on the battery and the starter.
====================================
You right on about cold starts. But don't your makeup freeze at -5 and fall off. So you can't be going out and there for don't need the Jeep to start anyway.:)

[RichP]

Rich, what is drydene? I still have a trutrac and auburn and 4.10's that I never got around to installing, including four bottles of gmc friction modifier that's like four years old (does the stuff have a shelf life?!?).

Drydene is a brand of lubricant, more on the commercial side, comes in 5 gallon cans like spackle. I think if it's still stinky it's still good :D :D :D

[RichP]

====================================
Easier winter starts, at -5f it spins as fast on the morning startup as it does the rest of the year which is easier on the battery and the starter.
====================================
You right on about cold starts. But don't your makeup freeze at -5 and fall off. So you can't be going out and there for don't need the Jeep to start anyway.:)

Mobil-1 grease takes care of that problem and it's red to start with :D

[mikeny59]

Rich, thanks

[Jay Welch]

Just an update if anyone is interested......

I just changed the oil again. It was weeping just a bit so I added 4 quarts of Valvoline 5W-30 and 2 quarts of Mobil 1 5W-30.

Not a drop leaking now so this is the blend I'll stick with in the future for this rig.

Jay in MA

..........Right after I changed the oil it started to drip from the rear main seal. I drained out 3 quarts of the synthetic and added 3 quarts of dino oil. The oil leak stopped for the most part. Next change will receive 2 quarts synthetic and 4 quarts dino.....if it still weeps it will go back to all dino.

[keep0njeepin0n]

x2

Do not put syn in your transmission unless it was made for it. Period. Once you start using syn in your engine I've always heard that you're not supposed to go back to regular oil either. I run mobil 1 in my yota and love the stuff...I still change it every 3000 miles and it's the same color as the day I poured it in. My father runs shaffer oil in his work trucks and likes it. It's a parrafin wax based oil, other than that I don't know much about it though other than the fact it was designed for use in the big rig industry.

I've heard this too but I'm here to tell you it's a bunch of crap and is totally NOT TRUE!!!!

Think about it, if it was true, why would they have synthetic blends, which is basically a mixture of syn oil and conventional oil.

Food for thought!!!!!!

[RichP]

I've heard this too but I'm here to tell you it's a bunch of crap and is totally NOT TRUE!!!!

Think about it, if it was true, why would they have synthetic blends, which is basically a mixture of syn oil and conventional oil.

Food for thought!!!!!!

Owners on here who have switched to synthetic oil in the AW4's have had mixed results,
worse case is they burn up in less than a 1000 miles, best case is the tranny works great. I've just gotten my first automatic in the form of a 97ZJ 4.0 Laredo, did the oil change 2nd day home with Mobil-1, did both diffs with Valvoline syn blend 140 gear oil, have not done the TC or the tranny yet but that coming first warm and dry driveway day I get time on the TC. The tranny I am not sure about, the fluid smells and looks OK and the tranny works well so far, it's a crap shoot IMO on that. I could do it with no hesitation IF I had the cash to put a reman in if it went tits up but as I don't and the holidays are coming up I'll leave well enough alone for now on that one. Besides I'm pulling the D35 and putting a D44 in there this spring so my mod money is kinda spoken for right now :D :D :D

[w_howey]

Owners on here who have switched to synthetic oil in the AW4's have had mixed results,
worse case is they burn up in less than a 1000 miles, best case is the tranny works great. I've just gotten my first automatic in the form of a 97ZJ 4.0 Laredo, did the oil change 2nd day home with Mobil-1, did both diffs with Valvoline syn blend 140 gear oil, have not done the TC or the tranny yet but that coming first warm and dry driveway day I get time on the TC. The tranny I am not sure about, the fluid smells and looks OK and the tranny works well so far, it's a crap shoot IMO on that. I could do it with no hesitation IF I had the cash to put a reman in if it went tits up but as I don't and the holidays are coming up I'll leave well enough alone for now on that one. Besides I'm pulling the D35 and putting a D44 in there this spring so my mod money is kinda spoken for right now :D :D :D


The people who have had the problems were the ones with trannies that were not cared for properly in the first place. A bad PO or lack of the correct maintence is the real culprit here. When the switch occurs the synthetic cleans out the crap that was already in there. That now freed up garbage is what creates the problem.

But as a loyal synthetic user, you already know that.

BTW, until I started selling AMSOIL I ran Mobil 1 in my junk also. All the T-cases of my herd still have Mobil 1 ATF in them. Never any problems whatsoever.

[Jim Mesthene]

Why would anyone want to spend any more money on Sin oil. You will never receive any payback for the extra cost.
The improved fuel mileage easily pays the difference in the cost of the oil. Measure it for yourself.