• Welcome to the new NAXJA Forum! If your password does not work, please use "Forgot your password?" link on the log-in page. Please feel free to reach out to [email protected] if we can provide any assistance.

30K AW4 Simple Question Drain vs. Drop vs. Flush

wescam

wescam

NAXJA Forum User
Location
Alexandria VA
I did search and read up, just looking for new opinions.

Anyway I got an 01 with 26K miles on it in Feb.

I just hit 30K miles.

I drained and refilled the transfer case with ATF +3.

I pulled the plug and refilled the AW4 with Dex III.

How "good" and "safe" are those auto tranny flushing machines.

Seems like (from searching) lots of folks with lower milage XJs are using them.

Anyone got any opinions of the flush? Any certain machine to look for at a mechanic?

Should I have done a pan drop at 30K?

FWIW, I llive in a very restricted apartment and can't do any work at home. I did this last bit of maintenance at my folks house in GA when there for a visit.

Thanks
 
the nice thing about the AW4 is that in place of the filter is a stainless steel metal screen that only needs cleaning once in a while. You are good to have just dump the fluid and refill. I do mine every 20K, but I use the toyota factory trans fluid(because im an ex-tech) and have tons of it... dex III is good enough..
 
The AW4 calls for DexIII. I have tried the ATF+3 in mine and it clunked harshly when coming & leaving a complete stop. Shifted the same though.
 
I would flush it. A good shop will run 18 quarts of ATF through it. Flushes are totally safe. It uses your transmissions own pump to do the work. Plus it gets roughly 95% of the crap out of the tranny. Drain and fill only get a third to maybe a half of the bad tranny fluid out. Just my two cents.
 
The only thing I was told to watch out for in a flush is if the tranny has been used hard and gotten hot several times leaving build up in the tranny. The new atf after a flush will break it down and may clog the valves. SO says my tranny guy anyway, I just drain the pan every so often and drop the pan about once a year. But my XJ is just for the trails, I never drive it on the highway.
 
I would flush it. A good shop will run 18 quarts of ATF through it. Flushes are totally safe. It uses your transmissions own pump to do the work. Plus it gets roughly 95% of the crap out of the tranny. Drain and fill only get a third to maybe a half of the bad tranny fluid out. Just my two cents.
Click to expand...

Not true you will never see a flush unit in a quality tranny shop, only in the speedy lube kinda places. I have seen trannys take a dive within several days of a FLUSH.


Gunner said:
The only thing I was told to watch out for in a flush is if the tranny has been used hard and gotten hot several times leaving build up in the tranny. The new atf after a flush will break it down and may clog the valves. SO says my tranny guy anyway, I just drain the pan every so often and drop the pan about once a year. But my XJ is just for the trails, I never drive it on the highway.
Click to expand...

X100 never flush a slush box if you are unsure of the condition of the fluid and if any gunk us in the pan. I have seen many trannys fali after a flush caused by junk being lodged in the valve assembly and causing overheating and other problem. all 4 tranny guys I know say never never never flush an automatic
 
Last edited:
I flushed my tranny in 99 GMC at 120k for the first time ever. It was the best thing I ever did. Shifted like when I bought it 50k before that. Now I have 155k on it still going strong. Same with my parents S10 blazer and lots of customers vehicles.
Plus if you only have 30k on and use BG chemicals from a dealer. They cover tranny repair in their warranty up to 100k. No questions asked. Just a thought. Tranny flush is recommended by dealers for a reason. Preventve maintence,a lot of old school thought and wives tales about it.
 
The machine type flush probably takes some cleaner chemicals, right? How about without, like dropping the pan, but more completely?

I've always done a change from the cooler lines - refill as it pumps itself out. You can see when the new stuff starts coming out, and based on volume, it's the full capacity of fluid. I've got hundreds of thousands of miles on mostly Fords (and my XJ) and never a problem with that method.

These aren't abused ones though, but anywhere from first fluid change to 250k miles on them. On older ones I'll add a bit of Trans-X and run it for a while first.
 
comancheon33 said:
I flushed my tranny in 99 GMC at 120k for the first time ever. It was the best thing I ever did. Shifted like when I bought it 50k before that. Now I have 155k on it still going strong. Same with my parents S10 blazer and lots of customers vehicles.
Plus if you only have 30k on and use BG chemicals from a dealer. They cover tranny repair in their warranty up to 100k. No questions asked. Just a thought. Tranny flush is recommended by dealers for a reason. Preventve maintence,a lot of old school thought and wives tales about it.
Click to expand...

Show me one automotive dealer who recommends this?


Ive seen 2 machines here locally and both of the return lines had tones of crap in them, The problem with the flush is the 18 year old noob operator making 7.50 an hour. If you do a google for problems after tranny flush you can find thousands of cases.

I had it done once on my 88 from a lube shop herein town, I did it just before a trip for the weekend, had it done thursday AM, After leaving the shop, it started acting up, (was fine before) would not shift crisply and lagged going into 4th. They refused to do anything about it. I got home and that night removed the pan, you could see tons of crap that had been forced into everywhere, Had to do a complete service that night, new screen and complete lower tranny tear donw and shot carb cleaner through it till it ran clean. I got nearly almost 1/2 a cup of crap out that I believe was not there before since I had dropped the pan and serviced only 6 months before. every time I do a deep water crossing I service the tranny as a precaution

I repeated the process once a week for 2 weeks till the screen was clean after running for a week
 
Last edited:
A transmission flush will not ruin your transmission... All the crap/neglect that has been in there will ruin a tranny... If you routinely service your transmission, then there should be no problem with having it flushed... I have flushed mine many times, and I have done flushs to hundreds of vehicles without a single problem...

Problems arrise when people neglect to service there transmission, then have it flushed. All of the sediment/debri that has accumulated in the transmission is mixed into the internals, and that is what causes the problems...

A drain/refil only service's 30-45% of your total transmission capacity [as a general rule - there are exceptions]. To completely 'remove' all/majority of the ATF a flush is necessary. Or if you like to take your transmission out, drain the torque convertor, and reinstall it be my guest...

ATF flush machines that use the transmission pump [read: have no external way to move the fluid through] won't use any more pressure than normal driving does... Do some reasearch on this subject... And if you choose to have a flush does, ask about the machine, and how it works... KNOW YOUR MECHANIC...

To answer your questions Wescam:

*Yes, a tranny flush is fine (I have done hundreds)
*A flush machine that uses the transmission pressure [BG come's to mind] is recommended.
*I would recommend a flush every 50-60K [depending on your driving conditions] with a drain and refill every 15-20K [again, depending on driving conditions]

If you have anyother questions, post them up... Or PM me...

Will.
 
From my experience and observations it appears that older cars taht have not been flushed or service regularly suffer the greatest potential for problems after a flush. Newer cars have no problem. If I had a new car and had regularly serviced it, I would have no problem with the tranny flush.
BSD
 
xjwillyb said:
A transmission flush will not ruin your transmission... All the crap/neglect that has been in there will ruin a tranny... If you routinely service your transmission, then there should be no problem with having it flushed... I have flushed mine many times, and I have done flushs to hundreds of vehicles without a single problem...

Problems arrise when people neglect to service there transmission, then have it flushed. All of the sediment/debri that has accumulated in the transmission is mixed into the internals, and that is what causes the problems...

A drain/refil only service's 30-45% of your total transmission capacity [as a general rule - there are exceptions]. To completely 'remove' all/majority of the ATF a flush is necessary. Or if you like to take your transmission out, drain the torque convertor, and reinstall it be my guest...

ATF flush machines that use the transmission pump [read: have no external way to move the fluid through] won't use any more pressure than normal driving does... Do some reasearch on this subject... And if you choose to have a flush does, ask about the machine, and how it works... KNOW YOUR MECHANIC...

To answer your questions Wescam:

*Yes, a tranny flush is fine (I have done hundreds)
*A flush machine that uses the transmission pressure [BG come's to mind] is recommended.
*I would recommend a flush every 50-60K [depending on your driving conditions] with a drain and refill every 15-20K [again, depending on driving conditions]

If you have anyother questions, post them up... Or PM me...

Will.
Click to expand...


again you assume that every place maintains thir flush machines perfectly. I will tell you right now most dont enve know the proceedures for maintaince on them.

You can find hundreds of instances just like mine that have occured. On my last rig had an aftermarket convertor with a drain plug, and an aftermarket cooler I could drain the entire system. which I did on a regular basis.

Im still waiting for an answer on which manufacture recommends the flush over the other method?
 
My guy uses the BG Machine, AWESOME DEVICE. Uses 16 qts and a special cleaner. Like getting a new tranny. I run Royal Purple Max ATF, it's a DexIII synthetic formula. Handles heat much better than any brand i've ever seen.
 
200K on my old one so far ('87 Cherokee) and NO oil changes (PO was a dilrod. Motor oil changed itself through leaks and he topped off and changed the filter once a year) but it still works fine. I have a back up ready to go in when this trans drops (I added STP engine oil treatment to it and added an inline filter that I've changed twice) I drove 2 miles to work and back every day and gave it to my daughter-in-law. Shop tried to suck her into a $2500 trans change! All it was causing trouble was the fuse was blown for the shift computer.
My son will get the 130,000K original mile well maintained 4.0L from my current '87 MJ and I'll have a 4.6L stroker with AW4 going in (converting to 4x4 at the same time. The 2WD BA 10/5 was Mopar rebuilt before I got he Comanche) It's getting a NP242, but I'd rather install a NV241 Rock Loc with 4:1 low range (like my BIG Jeep truck is getting) but the wife will be driving it.
 
Every new car maker suggests tranny flushes. Most at around every 30k. The flush machine doesn't hurt a thing. As long as it done properly and regularly. Plus with a good flushing agent it is awesome.
I myself would never trust my tranny to an oil change place only. They don't have a clue or care.There are at least 8-10 different types of tranny fluid on the market today. If you use the wrong stuff in your tranny You are just asking for trouble. Anyone that works at your local quick change oil place has no clue what they are doing. They only change oil for a reason. Just keep that in mind. My girlfriend can even do that.
If you opt to do the tranny flush, take it to a mechanic shop you trust. I do at 5-6 of these a week. No tranny failures to date. IMHO it is one of the best things that can be done to maintained vehicle.
 
comancheon33 said:
Every new car maker suggests tranny flushes. Most at around every 30k. The flush machine doesn't hurt a thing. As long as it done properly and regularly. Plus with a good flushing agent it is awesome.
I myself would never trust my tranny to an oil change place only. They don't have a clue or care.There are at least 8-10 different types of tranny fluid on the market today. If you use the wrong stuff in your tranny You are just asking for trouble. Anyone that works at your local quick change oil place has no clue what they are doing. They only change oil for a reason. Just keep that in mind. My girlfriend can even do that.
If you opt to do the tranny flush, take it to a mechanic shop you trust. I do at 5-6 of these a week. No tranny failures to date. IMHO it is one of the best things that can be done to maintained vehicle.
Click to expand...

still waiting for anyoen to show me in writing from any manufacturer where it states to flush for scheduled maintance
 
xjnation said:
still waiting for anyoen to show me in writing from any manufacturer where it states to flush for scheduled maintance
Click to expand...


yeah i agree i have done several tranny flushes (hundreds) and haven't had any problems because i always check the fluid first. if the fluid is thick, black, and stinking a tranny flush will ruin the trans but.... so will a tranny service on a vehicle in that condition. transmissions do get used to running with shitty fluid in them. so if all of a sudden it has new fluid everything frees up like it's supposed to but not used to. here's my question would you change your oil without changing the filter? no because? that's right all the new oil is going through an old filter contaminating the new oil. so why would you do this to your much more sensitive tranny? tranny flushes are not that bad to do if you perform regular maintenance on the tranny (filter changes) and do them at a halfway point between the pan services. but it really is just dealership snake oil. keep getting them though helps pay the bills. my .02
 
skipc said:
The machine type flush probably takes some cleaner chemicals, right? How about without, like dropping the pan, but more completely?

I've always done a change from the cooler lines - refill as it pumps itself out. You can see when the new stuff starts coming out, and based on volume, it's the full capacity of fluid. I've got hundreds of thousands of miles on mostly Fords (and my XJ) and never a problem with that method.

These aren't abused ones though, but anywhere from first fluid change to 250k miles on them. On older ones I'll add a bit of Trans-X and run it for a while first.
Click to expand...

skipc:
I'd really like to change all the transmission fluid out by tapping into the cooler lines... could you give a step by step description of how to go about doing it? Thanks.
jlex.
 
You must log in or register to reply here.

Similar threads

M
Oil pressure question
2
Replies
26
Views
3K
Money_Pit_Incoming
M
M
P0432 Code - 2001 XJ 4.0L – Auto – AW4/NP231 – 259K miles
Replies
0
Views
1K
Misternapps
M
M
New to my XJ & wrenching - How to choose parts and what to prioritize?!
2
Replies
28
Views
4K
flyin_ryan
F
E
Weirdness after cooling system refresh
Replies
12
Views
2K
boneheded
B
FernGreen
Aw4 Transmission Delayed Engagement
Replies
1
Views
1K
lawsoncl
L
Back
Top