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XJ Ask the Question Thread
CF Veteran

Joined: Apr 2011
Posts: 3,493
Likes: 0
From: Chickamauga Ga.
Year: 2000
Model: Cherokee
Engine: 4.0
That, or rms, or valve cover gasket, or oil filter adaptor o rings. I'd hit it with some purple power and get it really clean, se it will be easier to tell where the oil is coming from. I'd lean more toward rms or valve cover gasket for all the oil at the back, and oil filter adaptor o rings for the oil on the front passanger side of the oil pan/block.
CF Veteran
Joined: Apr 2011
Posts: 14,553
Likes: 1
From: Carrollton, GA
Year: 1994
Model: Cherokee
Engine: Inline 6 4.0L High Output
Decent purchase for U-joints and later on gear installs? http://www.harborfreight.com/12-ton-...ess-33497.html
CF Veteran

Joined: Apr 2011
Posts: 3,493
Likes: 0
From: Chickamauga Ga.
Year: 2000
Model: Cherokee
Engine: 4.0
RMS gets my vote...
Decent purchase for U-joints and later on gear installs? http://www.harborfreight.com/12-ton-...ess-33497.html
::CF Moderator::
Joined: Aug 2011
Posts: 43,971
Likes: 1,579
From: Prescott, Az
Year: 1990
Model: Cherokee (XJ)
Engine: 4.0
RMS gets my vote...
Decent purchase for U-joints and later on gear installs? http://www.harborfreight.com/12-ton-...ess-33497.html
Decent purchase for U-joints and later on gear installs? http://www.harborfreight.com/12-ton-...ess-33497.html
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. "$hit 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.
Revised 9-15-2012
CF Veteran
Joined: Jan 2012
Posts: 1,161
Likes: 1
From: Michigan
Year: 2000
Model: Cherokee
Engine: 4.0
anyone?
CF Veteran
Joined: Apr 2011
Posts: 14,553
Likes: 1
From: Carrollton, GA
Year: 1994
Model: Cherokee
Engine: Inline 6 4.0L High Output
Not really, how many times are you gonna install gears? And the best thing I've used for u joints is The ball joint/ unjoint press that they sell, you can't do ball joints with that shop press either, and id say you will change ball joints a lot more often than gears.
CF Veteran
Joined: Apr 2011
Posts: 14,553
Likes: 1
From: Carrollton, GA
Year: 1994
Model: Cherokee
Engine: Inline 6 4.0L High Output
Oil filter adapter seals gets my vote since the oil is forward of the area where the engine meets the trans. Here's the best way for ANYBODY to diagnose their oil leak.
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. "$hit 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.
Revised 9-15-2012
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. "$hit 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.
Revised 9-15-2012
CF Veteran

Joined: Apr 2011
Posts: 3,493
Likes: 0
From: Chickamauga Ga.
Year: 2000
Model: Cherokee
Engine: 4.0
You only have to press on the pinion bearings to do gears right? I'd say it would work, it would definantly work for u joints, and would be useful for one random thing or another from time to time. But it's big and expensive to be a one job tool.
CF Veteran

Joined: Apr 2011
Posts: 3,493
Likes: 0
From: Chickamauga Ga.
Year: 2000
Model: Cherokee
Engine: 4.0
::CF Moderator::
Joined: Aug 2011
Posts: 43,971
Likes: 1,579
From: Prescott, Az
Year: 1990
Model: Cherokee (XJ)
Engine: 4.0
I am trying to encourage the OP to do his own diagnosis and feel comfortable with his efforts. This ain't rocket science and we see too many people suggesting RMS immediately. Then some poor sucker goes to the expense and time involved to replace the rMS, only to find out his Jeep still leaks and suffering severe disappointment..
CF Veteran
Joined: Apr 2011
Posts: 14,553
Likes: 1
From: Carrollton, GA
Year: 1994
Model: Cherokee
Engine: Inline 6 4.0L High Output
True but im sure i will find uses for it... Where was the ball joint thing you were talking about?





