Hi, new to the forum here. I have a 1999 XJ with a 4.0L and AX4 trans. The jeep has been in my family since 30,000 on the clock. I just got it back from my sister. I am afraid to say with 99% certainty that she never had then AT fluid changed. I have heard around that since after 177,000 miles and no fluid change, it may be best to just let it ride. new fluid would shock the system. You guys agree? The trans actually runs well. Sometimes slams into gear alittle rough when going from reverse to drive, but shifts well. She also hasn't changed the transfer case or diff fluids either. What's your take on that? Thanks!

 

Change the fluid in the diffs and TC, now. On the trans, I have heard of the shocking the system thing, not shure I believe it, BUT. I would do a series partial fluid changes just to be safe, spread over a few thousand miles. Then I would do a full Fluid and filter change.

 

as the mans said just change whatsin the pan every few thousand miles and after awhile do the the lot

 

I did that to a 92 Dodge Shadow that had 98k and the tranny went out a month later. Everyone said it was coincedence but I don't know.

 

Id do what 93gc40 said and do it in steps. Then again I think youd be fine to change it all at once...Just flush it, maybe 2 or 3 times. I mean really how are you going to shock the system?... sounds stupid.

 

Change the fluid. Just use the right atf.

Just riding with old fluid is not smart. Try not to listen to myths like that, from people who have likely never even rebuilt an auto. Just about all the failures I've seen due to fluid changes have been because of incorrect atf.

 

^^^x2

Flushing a tranny after not changing the fluid for a lonngg time is a bad idea. Chanign the fluid shouldn't do anything bad at all. Flushing is only bad because it might loosen deposits and clog up the valve train.

 

If the transmission fails after servicing, it's only coincidence and would have gone out anyway. New fluid will help clean any varnish that has formed in the valve body. If I recall correctly the AW4 uses a screen as opposed to a filter as other Japanese automatics do. It doesn't require changing, but certainly can be . A flush recommended by Honda is a series of draining, refilling, driving around the block, and repeating four or five times. You can essentially do the same with the AW4. I'm not sure of the total fluid capacity of a dry AW4, but if it's 12 quarts, 5 drains and refills will give you about 87% new fluid. 6 would be 92%.

I would recommend that the first time that you drain the fluid into a clean container. If the drained fluid only contains small flakes that look like fine metal flake paint, continue the process. If it contains larger irregular shape debris, don't bother going any further. Just refill and drive it until driveability issues ensue.

I have over 225,000 on mine without a problem, and I only drain and refill periodically.

 

For everyone on the subject of the tranny fluid. Don't use ATF, use Dexron-III/Mercon...

 

Thanks for all the good advice guys.

 

Drop the pan and drain the converter if there is a drain plug. Use the
Dexron-III/Mercon like stated but do not take it to a shop and let them flush it. Call it a coincidence, myth or whatever. I honestly think if a transmission that has rarely or never been serviced suddenly gets stuck on one of those flushing machines it can and will force contaminates loose and they will get stuck in the valve body causing all kinds of trouble. I don't see it hurting the steels or any clutches but would raise hell with the valves and stuff in the valve body.
Have heard it for years and seen it from 2 people I know. Old car gets a flush job and the trans dies with in a week.
clint

 

Drain and fill with the correct fluid, the tranny should be fine. Do not go to Midas, or any transmission shop and have them flush it, you won't leave without buying a transmission. Just drain and fill it.

 

Cool, that's what I'll do. No flush, just a change. I'll report back on what happens. But check this out, I have known that the trans had too much fluid in it, so I let some out yesterday and got it back in the proper range at normal operating temp. This morning, I drove about 6 or so miles to drop my kid off. got back in it to go to work and started to feel a vibration in my gas pedal upon acceleration, but went away at cruising speed. it is possibly related just because I let out some fluid?!?! Is this in my head, maybe it's always been there?

 

I went to get an oil change from my mechanic on my 1998 olds and i said to do a tranny flush as well since it was never done. They said that i should not do it cuz of particles that break down are like internal clutch particles, idk. Basically said not to do it cuz they had a customer in the week before they told him the same thing, the customer said that they dont know what they are talking about, they went ahead and did a tranny flush the guy was back in 3 days for a new tranny...

 

I have a chevy, bought it with 148000 miles on it, I disconnected the tranny cooler line from the radiator and started the truck letting it pump out the fluid I only let it run for like 10 sec at time, them dump about four quarts back in it, and do it again until the fluid was coming out much cleaner. It had never been changed before and it was as black as motor oil. Its been running great for the last 20,000 miles. Ill probably do the filter soon now were talking about it lol