djlarroc

Good job!!

Don't use anything other than Dex/Merc III or IV!!

Even Chrysler says to use ATF4, but they are wrong

notop46

We planned on doing the engine oil first because it is long overdue. It is 2 WD so no transfer case, but I did forgot about the rear end. I do my oil every 4-5000 and all the other fluids (exept brake, clutch and PS) every 2 years (~20,000 miles).

It was over a gallon low on coolant when I checked it this weekend (I told him about checking the water level regulary when I replaced his radiator last year. Since I only see him when his Jeep needs repairs, it is hard to say how rapidly it is loosing coolant and how much water he has added (he tends to fudge the facts) between "visits".

Since I know he is loosing water, is there any way to tell if it is the gasket or the head? I know if we dont see it dripping, or spraying in the engine compartment or the heater core, then it will show up in the oil. Is it possible to leak to the combustion chamber (or intake manidold) and blow out with the exhaust?

Are there any other year cylinder heads from the JY that would be good candidates for replacing this one if it turns out bad? Local Autozone wants $380-460 for a replacement.

Thanks again for the insight and suggestions.

clacker

If i were you, i would definitly try to NOT cut that tubing if at all possible. unless the P.O. didnt have his normal services performed or either ran his tranny almost dry, there is no reason that the dipstick tube would be so stuck that it needed to be cut off

notop46

We did not have to cut the tube (see post #12). As for the condition of the transmission, re-read original post and post #16.

I'm still looking for suggested JY replacements for the 0331 cylinder head which may be cracked.

Thanks

notop46

I did swap out about a pint of my PS fluid when my daughter "parked" it in the ditch on its side for 3 hours.

https://www.cherokeeforum.com/member...lling-further/

tjwalker

2003 and newer 0331 heads from the Grand/Wrangler are fine.

They were built by a Brazilian Foundry (TUPY) and do not have the defective area between cylinders 3-4 that earlier 0331 heads have.

But you want to be absolutely sure that if you go that route, that it is a TUPY head. It is easy to know as the word TUPY is stamped into the head in the area of cylinder 3-4.

Good luck!

crystalion

I know this post is old but I saw somwthing here that people should know.

Lets also put aside all the electronics that are now on transmissions and stick to the unit itself.

Everyday there is a post about black trans fluid and "what do I do "-- "it won't shift"-- "am I screwed"! I'm amazed at how many folks aren't doing simple once a yr or 2yrs or more -tranny fluid changes--NOT FLUSHES or POWER FLUSHES since to me they are the same.

Before lock-up converters most all converters had drain plugs-so between draining the converter and dropping the pan and filter -you could get 90% of your fluid out.
Filters were either paper or metal screens-one would be thrown away and the other cleaned well and blown out (kerosene tank) then replaced.
By looking in the bottom of the pan you could guage how the unit basically was. A pan filled with friction material and metal powder was a good hint things weren't well but it doesn't mean death.

Power flushing on a tranny that has metal and friction material in it will spread it further into the unit -especially the valvle -body which will cause the valves to stick ( no shifts-slow shifts-lostgears).
On an older unit with black /burnt/ or just bad fluid --DROP THE PAN and see what is in there. On my 2000 AW4 there is what looks like a drain plug on the bottom of the pan and the dipstick tube entering it from the side also (PITA place for the tube). You can at least drain whats in the pan and refil with fresh fluid to gradually get some change going on. Still the better way would be to drop the pan and change the filter (if there is one to change). The converter will still be holding about 4 quarts ( depending on size) of fluid.

We used to disconnect the cooler lines from the rad and have 1 in an empty bucket and one full of fresh fluid to TRY to change out as much as we could ( because of no converter drain plug). 1 line is out of the trans the other sucks fluid back in.

Some trans problems (again no electronics involved)

Won't shift when cold -BUT will shift when HOT-
This was known as "Morning Sickness". The lip seals/ o-rings are usually ROCK HARD and can no longer hold the trans fluid pressure. Now as the car warms up the seals begin to soften and swell slightly and now will hold pressure allowing the drums to engage and shift. One quick way to cure this which usually ends the trannys life sooner than later is an ADDITIVE ( I havn't used or no anyone that used any newer products but I'll assume they are mostly the same-there may be some out there that aren't as harsh as they used to be). These are just chemicals that attack the rubber and make it soft and pliable BUT it usually goes to far and starts eating up whats left of the friction plates in the drums ( since the fluid is now like gasoline). Ever take a hose or piece of rubber and put it in MEK or Acetone for some time. It gets about 2X the size and as flabby as an old ***.

Won't shift when hot BUT will when its cold.
This is usually a clooged filter-as the unit runs the filter picks up more and more crap until it can no longer provide the tranny with enough fluid to work (low -pressure). The car will start slipping-won't shift. When the car sits the junk falls off the filter and back into the pan allowing some space for fluid to go through. Again the next morn it will shift OK then as you go get worse as the filter re-clogs up.


Your tansmission is an EXPENSIVE and has some delicate parts in there--I'm just amazed that people will change motor oil every week but NEVER change or replace the trans fluid- before its to late.

I know that now there are many other things to consider like a kick down cable ( which is far from new) the TCU and whatever else.
At $1,000- $1,500 for a good rebuilt unit today a few fluid changes now and then seems right.

I'm doing mine right now which I even let go a little to long but my fluid is nice and pink/red with no bad smells. With the summer coming and the extra heat-the extra things you'll be trying to put your JEEP through with the nice weather. Change that fluid !!