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Does Shell Rotella T still have ZDDP??

Question on the ZDDP--I heard that on a broke-in engine only 750-800 ppm is necessary?
 
That is still a valid question. Relatively low pressure valve springs, non-radical cam lobes = less pressure squeezing out oil film. But I have read a couple of posts of high mileage motors with wiped out cams. They didn't tie it in to any oil though. My guess is that 750-800 woulb be OK. Some say you need 1200. Open question. Just think of all the variables like heat treating/nitriding of surfaces, lifter/cam compatabity, thick oil start-up in cold weather, oil change frequency and much more.
 
15W40 is in fact thinner than 20w50(will also be better for cold starts). I'm thinking of switching to the Rotella T 15w40 here in the next week for the next oil change. Cheap and works great from what I've read. The mild cam's and flat tappet lifters in these 4.0's like the higher ZDDP. Anybody have a different opinion please chime in.
 
Mobil 1 extended performance with the gold cap bottle.

Actually, now that I check the 5W-30 extended performance has 800ppm. (which should be good enough) For 1200ppm, you have to go with the 15W-50 extended performance. They also make a 0W-40 which has 1000ppm, but I haven't seen that in stores here. That one would actually be the best. It is approved for Porsches and Vipers.
 
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winterbeater said:
Mobil 1 extended performance with the gold cap bottle.

Actually, now that I check the 5W-30 extended performance has 800ppm. (which should be good enough) For 1200ppm, you have to go with the 15W-50 extended performance. They also make a 0W-40 which has 1000ppm, but I haven't seen that in stores here. That one would actually be the best. It is approved for Porsches and Vipers.
Click to expand...


It's called the internet! haha, I'm sure you can find that 0w-40 online and for cheaper in bulk or something...

'Round here I might as well stick to the 15W-50, the average temperature here is high enough that the 15W-50 is about the same viscosity as a 10W-30 in colder environments.
 
Every time I see a thread on this subject its usually 100 pages long and the facts are all over the place...

I've been using Mobil 1 15w-50 in my 1991 XJ since it hit 120K miles... before that, I've always used Valvoline 20w-50 Racing oil. The last time I changed to Mobil 1 10w-40 High Mileage due to the perceived ZDDP issue. I just did a quick search on Mobil site and found the following.

It looks like I should have stayed with Mobil 1 15w-50.... see attached table.

You can use your own judgment if this is BS or not...

http://www.mobiloil.com/USA-English/MotorOil/Car_Care/AskMobil/Zinc_Motor_Oils.aspx

http://www.mobiloil.com/USA-English/MotorOil/Files/Mobil_1_Product_Guide.pdf

.
 
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The Rotella T is conv. correct? Any benefit to running the synthetic 5w40 besides the easier startup as far as the ZDDP is concerned?
 
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mrtosh said:
The Rotella T is conv. correct? Any benefit to running the synthetic 5w40 besides the easier startup as far as the ZDDP is concerned?
Click to expand...

benefit is less engine wear and longer change intervals, as well as a slower degradation of viscosity. I can't recommend putting it in high mileage/sludgy engines, as sometimes the sludge is all that's left keeping your rings/seals intact. The cleaning effects of a full synth will eat that sludge and your engine will die a slow death.

Also can't recommend a full synth for engine break-in, because everything needs to coat and properly soak up enough dino oil to be sealed and seated. Two oil changes with conventional should break it in enough that synth will be safe.

That's my plan with my new engine...
 
mrtosh said:
The Rotella T is conv. correct? Any benefit to running the synthetic 5w40 besides the easier startup as far as the ZDDP is concerned?
Click to expand...

At 260k I'm afraid I would start some leaks with 5w 40 syn.. not to mention loose oil pressure at idle.. I'm running 20w 50 right now.. and it does take a while to pump oil to the head.. maybe I could compromise with 10w 30, but I dont' know if there is any 10w 30 that has ZDDP..
 
winterbeater said:
The real problem is that the 15W-40 or 20W-50 is too thick for good cold startup oil flow. 80% of wear occurs at startup. A 5W-30 with ZDDP will protect better.
Click to expand...

^^depending on start up temps^^

the AMC Renix 4.0l (as recommended in the owners manual) shouldn't be operated above 60*F for extended periods on 5W-30.

20W-50 or 20W-40 for temps 30*F and higher
10W-40 or 10W-30 for temps 0*F and higher
5W-30 for temps 60* and below

I'll continue to run the 15W-40 Rotella unless I move somewhere where the ambient air temperature requires lower and rest well knowing I'm getting the Zinc I need and the protection the Renix was designed to have.:thumbup:
 
Using Synthetic oil after using conventional oils for several years isn't a wise choice, especially Mobil 1. First off conventional oils don't have the detergents like that found in Mobil 1 so it would start removing all the build up the motor has created over the years. Once that happens all your rings, oil seals and whatnot's will loose that seal created over the years and your engine will simply be a free flowing oil container without being contained in the right manner. My uncle made the mistake of using that oil after years of conventional and within 3 miles the vehicle was spewing smoke like a factory chimney, the motor needed rebuilt because all the buildup is removed and leaves the motor unsealed like mentioned above. Remember that is high mileage motors I am referring of.
Never use a detergent oil if you've never used prior in the same motor at high mileage.
Check with the original owner of the vehicle if possible to find out what they used as well to save yourself alot of grief.
I use Quaker State 5w30 here on Staten Island, NY and my motor never gets hot, starts regardless of temperatures outside. I live half a block from the ocean and yes tempatures drop well below 0 with the windchill.
 
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I've switched 100k mile motors over to synthetic without any bad consequences. If you read tests on the true tested viscosity of xxW-30 vs xxW-40 at vehicle operating temperatures, you will see there is virtually no difference. The difference is at startup. Don't forget that the owners manuals were written many years before the new oils were even on the market. If you want to know as much opinions about oil as is possible, go spend a few weeks reading forums on www.bobistheoilguy.com.

What I think is funny is how opinions vary with some people trying to flush out perceived gunk with thinners and transmission fluid, MMO, whatever, and others wanting to run super thick oil.

The main reason I swiched to synthetic was to increase time between oil changes, because my collection of old drained oil was getting to be a mess. Yes, I know I can take it in to the oil change stations.
 
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