Changing trans fluid and filter?????

[XJEEPER]

I am scared to change the filter and partial fluid now. 2 other people outside this board said if it isn't broke don't change it. they claimed they knew 2 people that changed their fluid and filter and ended up with their trans going out in a day or two. They were not Jeep's. I have 110,000 miles and have no idea if it has been serviced before. the fluid is a golden brown. Not really smelly. This vehicle is going to be my only mode of transportation in a week and I don't have money to fix a trans. What should I do??????

This logic is retarded at best.
The two worst things on an auto tranny are excessive heat and excessive heat. A happy, healthy auto trans likes 180-230 degrees, running it hotter than 240 on a regular basis will not only breakdown the lubrication properties of the ATF, but deposit varnish (think cooked oil) which will impair the tranny's functions.

Over time, heat breaks down the fluid, which is why it's looking brown instead of red. Since you have no idea on the fluids history, start now with fresh fluid and new history. A fluid change won't kill your tranny if done properly, no harder than changing your oil, just few extra steps. Not changing your fluid WILL dramatically shorten it's lifespan which should be 200K + miles on your AW4, if take care of properly.

BTW, I have a buddy that owns a 2nd gen tranny repair shop and his shop is always very busy and his prices are about 10% higher than other local shops because he doesn't cut corners on his rebuilds.......you pay to do it right or take it elsewhere.
He does not powerflush tranny's nor recommend the process.

He does however, repair alot of trannys that have recently been powerflushed by other local shop, mainly because the powerflush process dislodges varnish and crud that can build up in a poorly maintained tranny and plug passageways and check balls in the valve body. (Kind of a lucrative scam,eh?......I powerflush your tranny, it starts acting up a few weeks later, I charge you for a couple thousand $$$$ rebuild!)

 

[5-90]

This logic is retarded at best.
The two worst things on an auto tranny are excessive heat and excessive heat. A happy, healthy auto trans likes 180-230 degrees, running it hotter than 240 on a regular basis will not only breakdown the lubrication properties of the ATF, but deposit varnish (think cooked oil) which will impair the tranny's functions.

Over time, heat breaks down the fluid, which is why it's looking brown instead of red. Since you have no idea on the fluids history, start now with fresh fluid and new history. A fluid change won't kill your tranny if done properly, no harder than changing your oil, just few extra steps. Not changing your fluid WILL dramatically shorten it's lifespan which should be 200K + miles on your AW4, if take care of properly.

BTW, I have a buddy that owns a 2nd gen tranny repair shop and his shop is always very busy and his prices are about 10% higher than other local shops because he doesn't cut corners on his rebuilds.......you pay to do it right or take it elsewhere.
He does not powerflush tranny's nor recommend the process.

He does however, repair alot of trannys that have recently been powerflushed by other local shop, mainly because the powerflush process dislodges varnish and crud that can build up in a poorly maintained tranny and plug passageways and check balls in the valve body. (Kind of a lucrative scam,eh?......I powerflush your tranny, it starts acting up a few weeks later, I charge you for a couple thousand $$$$ rebuild!)

Ayuh. You did forget the third leading cause of automatic transmission failure - excessive heat. (Yes, I'm trying to make a point. It's painfully easy to cook a slushbox to death...)

Powerflushing a transmission is overkill, for reasons stated. If I think I've got that much crap built up in the box, I'll just tear down the valve body for cleaning, and get a "friction kit" to replace the clutch packs. As XJEEPER said, it's a great way to dislodge something and have it stick somewhere it don't need to be. Have you ever see the transmission's valve body? Lots of little hydraulic passages and check ball locations, and just some strainers that are smaller than thimbles to filter the fluid (the primary filter don't do much - I plan on adding "spin-on" filters underhood one of these days.) If your valve body is just that crapped up, it's a lot easier on you to get a basic rebuild kit (valve body gasket, seals, strainers, and check balls) and get the crap out of the box that way. Make sure you have a Polaroid or a decent digital handy so you know how everything goes back together (there's a reason a Polaroid lives in my toolbox...)

In short, if you suspect buildup, you're going to be a lot better off getting it out of there gradually than just "blowing" it loose and hoping you get it all. Once you've gone through a case of fluid (should be about three changes,) you can think about adding a transmission flush of some sort - I've always preferred Berryman's B12 "Chemtool" for light duty cleaning.

5-90

 

[falcon556]

XJ owners are lucky to have the AW4 instead of the crappy Chrysler they use in the Grand Cherokees.
I think the AW4 can keep going for ever as long as it keeps its cool.
Heat is the worst enemy, (the fourth reason for failure) :-D
I have installed transmission coolers in my XJs and had very good luck so far.

 

[Windrider]

One pointer.

Fill til you hit MAX on the dipstick. I was little lazy when I did mine and stopped at 1/2 way between the add and MAX line (above the OK) and had a little problem with the tranny dropping into and out of first when stopping and starting off with anything more than a light foot on the brake of accelerator.
(It happened to be that I ran out of tranny fluid at that point.)

I drove it maybe 1,000 miles like this right after I bought it so I didn't know how it usually acted. (It had some major rear axle issues for a while and I mistakenly figured that was the problem.) It didn't happen all the time but it did happen most of the time and it varied in intensity.

I topped it off with more fluid to exactly the MAX line. Problem appears to be gone.

So, make sure you get as close to the MAX line as possible.

 

[53guy]

like a few people have stated, don't do a power flush. the poblem with the power flushes is that it pushes fluid backwards. think of how long and hot the fluid has been pushing the seals one way and then some 'tard at a tranny shop pushes it the other way?!? what a great way to unseat all the seals in the tranny. i got a jeep at one point who the owner did that and within 1000 miles, the tranny was crapping itself. just don't do it.

 

[Fish'nCarz]

Great. A new thing for me to worry about now.

Speaking of spin-on filters though, I just found a super spin-on filter/tranny cooler rig on a police package crown vic at the you-wreck-it yard. The hoses looked like the hydraulic hoses and fittings on a front end loader, though. How big a job would it be to replace the little tranny hose fittins on my XJ with these monsters? Would adapting the fittings to match the jeep be a better path to take, or is it just a bad idea to try to use this part?

 

[lawsoncl]

Two tips. Watch out when you pull the filter as it will dump more fluid (it tastes nasty, btw). Go easy on the pan mounting bolts. They don't thread very far into the aluminum case and strip very easy. The previous owner of my ZJ stripped a few of mine and glued the bolts in with silicon. I fixed it by re-tapping the holes with a 1/4-20 forming tap I had handy, but it means I have to pay attention to what bolts came out of which holes.

 

[XJ4PLAY]

2 other people outside this board said if it isn't broke don't change it. they claimed they knew 2 people that changed their fluid and filter and ended up with their trans going out in a day or two. They were not Jeep's.

I had this happen to me on my wife's GMC Envoy.
Power flushed it, for general maintenance, 2 weels ago and today reverse is gone and it sounds like tranny and or transfer case not engaging properly in drive gears.
I will get a full story during the week, but no more power flushes for my vehicles!!

 

[Boatwrench]

Hmmm....The flush machine we had at my former employer needed the engine running, which meant the trans pump was moving the fluid, so it could not have been backwards. It was more like a transmission fluid transfusion. We increased the distance between transmission failures on a city transit bus and support vehicle fleet performing this task every 48K miles. Prior to that it was just drain the pan and refill every 12K miles. Transmissions would last about 75-80K miles and we increased it to 130K average.

I like the flush machines. Just my opinion.

Tom

 

[mdicanio]

I am new to this site and think it is really informative. It already has helped me a great deal. Thanks to everyone!

Anyway, I have a 99 Cherokee with 123,000 miles on it. I assume I have the AW4 tranny. I have been changing the fluid every 30K by draining the pan and refilling it. I have been using Mopar ATF+3. I am at the point where it is time to change it but was told by a local repair/body shop to stop changing it after 90K. The guy that told me this has a 96 Cherokee with almost 200K on it and has had no problems. He works on may Cherokees in fact and has never had any complaints with this logic.

I firmly believe that the fluid should be changed every 30K but I have heard many say that they never change the fluid because the new fluid if more acidic and will cause the tranny to fail by weaken the seals. These people don't own Jeeps though.

One of the mechanics at the dealer I bought my Jeep from said to change it every 30K and I would never have a problem.

Who is correct? My Jeep is paid off in a month. I'd hate to have the tranny crap out now.

 

[fender]

I am going to do my first fluid change on my 98 over the course of the next few weeks and am a bit nervous myself.
I plan on draining and adding about a quart at a time each week for about 6 weeks or so. I have gone 190K without a change or any additional fluid added and figure I should probably make a gradual change. At the moment I am battling with "If it ain't broke..." and "190,000 miles on the SAME FLUID!!!!". I don't think I will swap the filter (the local parts stores can't seem to find the right one) until maybe I hit 200k

 

[lawsoncl]

I'd probably change maybe 2 or 3 quarts at a time, but yeah that sounds like a plan. The "filter" is just a real fine mesh screen. It's not like paper or cloth that plugs over time. If you have to pull the pan for anything, change it, but otherwise don't worry about it too much.

 

[Fish'nCarz]

I just drained and refilled my '01's transmission fluid Monday. About 3+ quarts come out easily, along with a little swarf (not much, but I didn't want to see any.)

My only problems were reminding myself to go easy because the drain plug threads into SHEET METAL, not a casting, and the 'no-splash' funnel I bought at harbor freight is just small enough to fit in the filler tube. I needed to hold the funnel with one hand and pour ATF out of a gallon jug with the other.

I'll do that one more time before winter to see if there are any more little crumbs in there. Tranny works more smoothly than ever now. I'm still thinking a screw-on type oil filter on the tranny somewhere would be a really good idea.

 

[falcon556]

Anyway, I have a 99 Cherokee with 123,000 miles on it. I assume I have the AW4 tranny. I have been changing the fluid every 30K by draining the pan and refilling it. I have been using Mopar ATF+3. .

ATF+3 in a AW4? Why? How come? What's the deal? Why?
Did I remember to ask you why?
The manual specifically states DEXRON.
If you needed to use Chrysler ATF why +3 instead of the superior +4?
We are talking about a regular XJ Cherokee and not a Grand Cherokee,
correct? The AW4 is a good transmission and it was made to use DEXRON.
I have a 99 and would never use ATF+.

 

[falcon556]

I am going to do my first fluid change on my 98 over the course of the next few weeks and am a bit nervous myself.
I plan on draining and adding about a quart at a time each week for about 6 weeks or so. I have gone 190K without a change or any additional fluid added and figure I should probably make a gradual change. At the moment I am battling with "If it ain't broke..." and "190,000 miles on the SAME FLUID!!!!". I don't think I will swap the filter (the local parts stores can't seem to find the right one) until maybe I hit 200k

So you prefer partial changes.
The way I did it was to collect the old fluid, accurately measure the amount, and replace it with the exact same amount of fresh fluid.
This avoids any chance of overfilling. To check the level take it for a ride, a few miles later when it is hot, check.

 

[mdicanio]

Regular XJ, NOT the Grand.

I went directly to the dealer and that is what they gave me at 30K, 60K, & 90K. At 90K I got the last of the ATF+3 from the dealer I normally buy it from. ATF+3 is no longer available and ATF+4 now replaces it. The mechanic I spoke to at the dealer said to stick with the Mopar stuff and never buy it at a place like Walmart.

I will check my manual but I don't remember anything about Dexron. If I was to get Dexron, I would not even know where to buy something like this other than Napa. I don't trust buying tranny fluid from Walmart or Autozone.

If it does say Dexron in the manual I think it is a little late to worry about it now. It has been running for over 100,000 miles with the ATF+3 mixed with what may have been Dexron to start. I don't know if it is possible to go back with out pulling the pan and filter.

 

[Fish'nCarz]

From the FSM

"Mopart Dexron IIE/Mercon is the recommended
fluid for the AW-4 automatic transmissions."

 

[langer1]

The Chrysler ATF+4 is not a replacement for +4. It's only to be used in transmission made for +4.
The AW4 is not made by Chrysler and is made to use Dextron/Mercon II/III.

 

[falcon556]

The Chrysler ATF+4 is not a replacement for +4.

If you say so.

To those with Chrysler transmissions you can buy aftermarket ATF+4 such as Valvoline. It is made under a Chrysler licence and therefore OK.
Cheaper too.

 

[falcon556]

From the FSM

"Mopart Dexron IIE/Mercon is the recommended
fluid for the AW-4 automatic transmissions."

There is a service bulletin regarding the use of ATF+4 and it does not include the AW4.
ATF+4 is an excellent synthetic fluid, unfortunately the AW4 can't use it.
I use it in my transfer case.