cole93maxxxj

ok so i just recently finished my complete rebuild on my aw4 automatic thansmission! and i filled it with valvoline atf+4 thinking it would be good for my tranny that i had just spent 400+ bucks on! and it couldent even get out of its own way ! i did some reasearch and found that "they" tell you specificly not to run synthetic in your aw4 trannsmission, and that its actually too good for your transmission! the clutches slipp too much and gaskets leak by and stuff because the synthetic is just too slippery! so i flushed it all out w regular wallmart atf and it runs like a chap now!

So i just wanted to make this thred to warn anyone from making the same mistake i did!





^^^^^^ bad ^^^^^^


^^^ GOOD ^^^^

redmuck

i thought i read here or somewhere that the aw4's dont use the atf4 because the tranny is japanese made not chrysler. the mercon 3 or 4 is for japanese or imports and some american cars. anyone correct me if im wrong.

Hylander

Manual calls for Dexron III/Mercon

okcjeeper

Yep Dexron/Mercon III or better. ATF-4 is a big no no in our AW4's.

UserID6095

Cole do you live in Brentwood Cali? Next to Oakley and Antioch? 94513.

Not a creep-o question.

5-90

The problem has nothing to do with synthetic fluid - I've had three AW4s that were fed a steady diet of synthetic Dexron without issues for upwards of 100Kmiles.

The problem was with ATF +4 - it's a ChryCo-spec fluid for their later-gen autos (with names like 37RH, 42RE, &c. The earlier ChryCos - A727, A904, A998/999, et al also used Dexron/Mercon spec...) being used in the first place. The AW4 is a Toyota box, and Toyota boxes have pretty much always used Dexron-spec fluids (the AW4 drain plug even has "DII" stamped into the head.)

EndlessMtnFab

Everyone else pretty much summed it up.


There are dozens of posts saying NOT to use ATF +4 (synthetic or otherwise). I've used synthetic Dexron with nary an issue on many customers vehicles.


Sorry for your misfortune.



Joe

JeepCoMJ

I ran synthetic dex in my old 87 comanche, and a friend put it in his 95 cherokee.

I replaced both transmissions within 2000 miles of swapping to synthetic...and it was spec. fluid, but synthetic.

both transmissions stopped shifting altogether. and trust me, i'm no dummy...I know what i'm doing when it comes to working on xj's and mj's.

I'll NEVER run synthetic in an aw4.

whowey

For my customers I always recommend staying with a conventional Dex III for older, non-rebuilt transmissions.

But synthetic Dex II/III is fine for fresh rebuilds or new trannies.

xjrev10

no amsoil products in the tranny then????

deltatechx

good thing I saw this. I was about to buy a 12 quart case of Amsoil's Universal Synthetic Transmission Fluid to do a full flush!! How do other Amsoil products fair in the XJ? My plan was to switch all my fluids to Amsoil: PS, DOT4 brake fluid, 5w-40 Full Synthetic, and Severe Gear 75w-90 for both the differentials (open gear, not posi). Should I be ok using these fluids?

5-90

Mixed results in synth engine oil - while it's got more lubricity to it, it is also more detergent - and it can flush out crud that is backing the seals. Won't cause engine trouble, but you may end up replacing any or all of: front main/rear main/valve cover gasket/oil sump gasket/timing cover gasket. This will be due to crud being washed out, not due to inherent trouble with the synth oil.

Stick to DOT3 on the brake fluid, unless the AMSOIL DOT4 is specifically listed as compatible with standard DOT3. Or, flush out the system and replace every bit of rubber in it (including piston seals) before filling with DOT4. As I recall, the two fluids are incompatible (I may be wrong, but I find this a safe thumb rule to follow.)

Gear oil? No trouble with your gears - but seals may encounter a similar problem to the engine seals. Ditto power steering (although, to simplify the logistical train, I end up using Dex in the power steering once I've pulled most of the old fluid out, or replace major components. No trouble - and it's one less fluid I have to keep track of and on hand.)

EndlessMtnFab

What you are describing applies to DOT 5 .... not DOT 4



DOT 3 & 4 can be mixed together.




Joe

xjrev10

whowey will school ya

whowey

A vast majority of the problems that the community has seen with AW-4's and synthetic fluids have been in worn transmissions. Technically its not a problem with the synthetics OR a problem with the transmission. Its a problem with the combination of the two. The synthetic fluids have a higher lubricity than conventional fluids. So that combined with parts that have been broken in on conventional fluids, there have been transmissions that have started slipping. The problem hasn't been seen on new rebuilt transmissions, only ones with miles on them.

Delta... I will pm you the rest of my answer to your questions. I don't want to threadjack the OPs thread any worse than I already have.