Hello everyone. I have a 1993 Jeep XJ that I bought off a friend last September. He let the Jeep run without coolant, which ended up cracking the head gasket. We tried to do a head gasket replacement, but the engine was too far gone. I went ahead and got a 1995 Jeep Wrangler engine from the junkyard and installed it into the Cherokee. It had been running fine for a few weeks when I noticed that it would start shaking violently once it was going into overdrive. I also noticed that there was a huge oil leak coming from where the engine and transmission meet. To address the violent shaking during OD I went ahead and did the following repairs:

Replaced Torque Converter
Replaced Transmission oil, pan gasket, and filter.
Changed out fuel filter
Cleaned fuel injectors
Changed Sparkplug wires, rotor and cap, and sparkplugs.
Replaced entire distributor
Replaced Fuel Pressure Regulator
Replaced TPS
Replaced IAC
Replaced Fuel Filter Adapter Oring
Replaced Valve Cover Gasket.
Replaced Oil Cap
Replaced oil pan gasket (2 times)

Despite all these repairs, the jeep still shakes violently. I also went ahead and replaced rear main seal twice now, and the oil is still leaking from the rear main seal area. Just want to know if anyone has any idea why this Jeep is falling apart. Ive followed several Youtube videos on replacing all parts, and have been meticulous.

 

Andres,

Was it doing this before you got the car? If it is violently shaking you may have some death wobble issues considering the age of the truck. I know there are a bunch of threads on death wobble here.
- Tie Rods
- Ball Joints
- Track Bar
- Alignment

Those are some start points. I don't know if your truck has a small lift but I got pretty bad wobbles with a 2" BB lift since all my stuff was worn at about 250k.

As for your oil I would check the valve cover because it tends to leak from the back and drip down. If it is the rear main seal leaking again, you need to take the main cap near the back of the motor again and make sure you use permatex anaerobic sealant to make sure everything seals correctly. There are also more instructions in this forum for that type of job. Or, it could be your tranmission front seal if you nicked the seal when you put the torque converter in. Clean it and make sure it is actually motor oil.

Hope this helps.

 

I installed one of these in mt 89 last year and it looks like it finally put an end to the valve cover leaks!
These are not cheap but they work.

🤔

 

just on the oil leak, unless you have absolutely verified the oil adaptor o-rings are not leaking (normally by replacing them) they leaked an enormous amount of oil on all my XJs

to verify, degrease & wipe down adaptor & oil filter area till perfectly clean, run engine for a couple of minutes, should be no oil dripping down side of block or of filter

 

I'm thinking the flexplate is loose on the crankshaft, especially because you probably changed it from the Wrangler to the Cherokee one. Just a hunch.

 

CRUISER'S MOSTLY RENIX TIPS

REAR MAIN SEAL DIAGNOSIS

OCTOBER 31, 2015 SALAD 2 COMMENTS EDIT

I’d be looking up ABOVE first, and VERIFYING the source of the oil leak YOURSELF.

Everybody, who doesn’t own or have to pay for or perform your vehicle repairs, loves to poke their noggin UNDER the Jeep and come out bearing the false bad news that your RMS is leaking. Many mechanics, friends, and good old Uncle Bob seem to enjoy telling you it’s the rear main seal. Has a catastrophic ring to it, doesn’t it?

A simple leak at the back of the valve cover or other source could produce the same symptoms. You don’t need to be a mechanic to figure this out. If you have good eyesight and a dim flashlight, you’re good to go on your own. Don’t jump on the RMS/oil pan gasket bandwagon right off the bat.

Almost any oil leak on your 4.0 is gonna drip from the RMS area for two simple reasons:

First off, the engine sits nose-up and any oil will run back to the RMS area.

Secondly, the RMS area is also the lowest point on the engine. Simple physics and the old plumber’s adage apply here: “Crap flows downhill”.

Valve cover gasket, oil pressure sending unit, oil filter adapter seals and distributor gasket, in that order, have to be eliminated as possibilities first. A little tip here. Rather than use a dizzy gasket, use an o ring instead. NAPA #727-2024. Tips 12 and 13 will help you get your distributor back in place correctly.