Tranny pan and filter change

I'm about to drop the pan on my tranny, as well as flush all the fluid out.

Anyway, I remember hearing something about the dip stick tube making it a PINA to do??? Can anyone elaborate on what I'll be up against?

Also what should the pan bolts be torqued down to?

It's a 1996 4.0 AW4 XJ

Thanks!!

Unless you see a lot of metal when you drain the fluid, dropping the pan is not strictly necessary. I drain my transmission fluid so that it flows over a magnet to check for bits of steel - those are the important bits anyhow...

For flushing, I usually use a pint bottle of Berryman's B-12 Chemtool - run for about 1/2 hour or so (try to hit all gear ranges manually) and drain hot. Top off with four quarts of Dexron II/III and yer good to go!

The filter for the AW4 is just a screen (think "sump strainer,") and doesn't filter much. If you really want a decent filter, change the setup up front to accept a remote "spin-on" filter, and put in a remote cooler while you're at it. The sum strainer works about like draining your cereal bowl through your teeth - if it's not big enough, it goes right thru - but won't cause much of a problem (I've torn down a few of these boxes now, and even with high mileage they look pretty good inside...)

5-90

I dropped the pan on my 96 a few years ago, and the dipstick thing did make me mad. I just kept twisting and pulling and it finally came apart. Wasn't too bad, took about 10 minutes of pulling.

Jackhill442 said:

I dropped the pan on my 96 a few years ago, and the dipstick thing did make me mad. I just kept twisting and pulling and it finally came apart. Wasn't too bad, took about 10 minutes of pulling.

Click to expand...

why did you need to pull? what was holding it up?????


ETA, if all the filter is, is a metal screen, do I need to worry about the quality (brand) of the filter??

NAPAs is 39.99 and is made by Micron Technologies or something similar to that. Car Quest's is $26.something and made by Wix. I know Wix mades good oil filters, so I was leaning towards the Car Quest kit.

But then again you get what you pay for, which is making me lean towards the Napa kit, although I've never heard of them, I assume they are good quality?

I wouldn't bother with either. Go with a remote "spin-on" kit and you'll make your life easier by a couple orders of magnitude... Besides, a full-size spin-on filter will probably give you more filter area than a sump strainer, and all the sump filters I've seen were steel screens anyhow. No point in buying a replacement there. Keep the screen "as are" and use a full-sized remote filter - it's on my list of mods...

5-90

When I changed my '01 at about 50k miles, I found virtually nothing in the pan or filter. The magnets had a little crap on them, but nothing like I have seen in other makes of tranny. My XJ had a hitch on it that was removed before I bought it, so it was probably used for some towing. The AW4 is one tough tranny. My fluid was dark and nasty so that definately needed to be changed, but I felt silly for dropping the pan and changing the filter after I did it. I think periodic drain and fill and maybe an occasional filter change should be more than enough to keep the AW4 happy under most conditions. People told me that before I changed mine but I have to learn everything the hard way for some reason.

Edit: I bought the filter at Advance Auto Parts for about $16 IIRC, and it had a stainless screen just like OEM. It was a Pro-King FK-227.

The dipstick tube is connected to the tranny pan by an o-ring; disassembly consists of pulling with a little twisting to get it out but reinstallation may take a bit longer, especially if you're fighting a pan that's covered in RTV. It's not necessary on all models and lift combinations, but you may find it easier to remove the front driveshaft in order to get some more room to slide the tranny pan back in.

Since some genius decided to put the pan drain at a high point in the pan, there will be a considerable amount of fluid in the pan when you're removing it...I hope it's not too hot as it pours down your arm!! There are two magnets inside the pan, make sure they get removed and cleaned before reinstalling them in the same recesses.

Unbolt the tube from the bell housing. It's one 1/2" bolt. Then pull out the pan with it attached. THEN you can remove it easier. Then put the pan back on and reinsert the tube from the top. I've done it both ways and this way was the easiest.

Wobbles - that's my plan for when I'm planning to re-do my tranny pan or drop the tranny...whichever comes first at this point.

Well we a friend and I did it. We found it impossible to separate the pan from the dipstick tube, so I unbolted it from the bracket. The bracket ended up getting very bent over the whole ordeal.

Took about 45 minutes to get the pan separate from the jeep. Pulled it down with the dipstick tube still attached.

Gasket broke; luckily we had another one handy. Worst thing was one of the bolts got snapped off, leaving a piece lodged into the threads. The threads for another bolt got stripped out as well. And last but not least, in the confusion of everything the wrong sized bolt was used while screwing the last bolt in. It was a very awkward angle, and the oversized bolt ended up threading in sideways.

How can this be fixed to the point the pan can be serviced again?

Oops...

The transmission body is (as you have probably noticed) aluminum, and that can work in your favour. Catch is, you'll need a set of M6x1.0 Heli-Coils or similar (don't use threaded bushings, there's not a lot of meat to work with there. Re-Coils will also work.)

You can just drill out and install the coil in the stripped bolt hole, but you'll have to remove the broken bolt before you can fix that. Any idea why it broke? Was it crossed, or just weak? It is usually easiest to weld a stub of something onto it so you can get a grip, but you may not have room. I'd use a left-hand twist drill bit to try to grab the bolt - start with a middlin' high speed to start the hole, then go to a low speed to grab it and spin it out. The LH bit usually works better than EZ-Outs (also known as Snap-Off Tools.)

The oversize hole? Depends on how oversize it is. If it's not too bad, you can still use a Heli-Coil; elsewise, you'll probably need to drill and tap oversize. Something to check in to - you can check it with the bit and tap that comes with your Heli-Coil set.

I've probably seen about the best consistent prices at MSC Direct - www.mscdirect.com.

5-90

One of the bolts that stripped out, because of the oversized bolt that went in sideways, is right above the exhaust. This makes it extremely hard to get to. Will it still be possible to helicoil it?

5-90 do you know any local type stores that carry helicoils? The holes to my tranmisison mount are stripped out.

Check your hardware stores or machinist's supply stores - I can get them at Orchard Supply in limited sizes (local hardware chain) and I can go into Santa Clara and hit some MRO shops for them.

I mentioned MSC because they're usually cheaper than everyone local (that cna be an issue sometimes) and it looks like you're a lot closer tothem than I am (they're in NYC or thereabouts, I seem to recall.) A couple phone calls will probably turn up a few around you...

5-90

Well I was able to fix it this afternoon. Used a small pair of channel locks to twist the snapped bolt out, and replaced the stripped bolt threads with slightly oversized bolts.

Shouldn't have much of a problem servicing the pan again.