Oil Cooler

Anybody ever add an Oil Cooler to their Jeep ?

If so what type did you use? ie. remote cooler etc.\

Did it lower you're oil / engine temp very much ?

Every 4 x4 I have ever owned had an Oil Cooler except for this Jeep... Its a 93' model....

Oil coolers aren't very common on Jeeps because they are designed for off road. unlike other SUVs that never saw a speck of dirt in their life...
As such, things can cause problems....rocks, branches and the like. Since oil is the life blood of any engine, anything that risks the circulation of that "blood" is avoided. Oil coolers can be very dangerous.
Another reason for not using an oil cooler on a Jeep is that that 4L straight 6 engine has a oiling problem with the cylinders at the back of the engine...The engine needs every ounce of pressure to keep those back cylinders oiled. Adding an oilcooler, adds resistance to the system...sure, the oil pressure may read fine, but is it reading inFRONT of the cooler or after the cooler?
And unless you live in really harsh environments (like deserts and such where average temps are over 100 F) the oil cooler really isn't needed.
Ed
web/gadget guru

Oil coolers aren't very common on Jeeps because they are designed for off road. unlike other SUVs that never saw a speck of dirt in their life...
As such, things can cause problems....rocks, branches and the like. Since oil is the life blood of any engine, anything that risks the circulation of that "blood" is avoided. Oil coolers can be very dangerous.
Another reason for not using an oil cooler on a Jeep is that that 4L straight 6 engine has a oiling problem with the cylinders at the back of the engine...The engine needs every ounce of pressure to keep those back cylinders oiled. Adding an oilcooler, adds resistance to the system...sure, the oil pressure may read fine, but is it reading inFRONT of the cooler or after the cooler?
And unless you live in really harsh environments (like deserts and such where average temps are over 100 F) the oil cooler really isn't needed.
Ed
web/gadget guru

Thanks for you're reply,

Well I do live in Texas and it gets hot here... I have a V8 318 and it runs hot... 210 degrees as long as you are moving but as soon as you stop it gets real hot real quick..

I have taken the Jeep to 3 different shops and a Jeep Dealer and none of them can tell me why it is overheating...

The Radiator, Water Pump, Thermostat, and Fan Clutch are all new, they were replaced by the person whom I bought the car from..
The system is very clean... It has been flushed using the reverse flush method and the chemical flush...

All of the shops suggested an auxillary fan and/ or an oil cooler but I really do not know what to do...

I have a remote filter / 17" cooler on mine. Ran stainless steel hose braced to the block and mounted everything up high to keep it out of trouble. I bought my Perma Cool cooler and remote kit from Summit Racing and hoses from Napa.

I have a remote filter / 17" cooler on mine. Ran stainless steel hose braced to the block and mounted everything up high to keep it out of trouble. I bought my Perma Cool cooler and remote kit from Summit Racing and hoses from Napa.


How well does it work as far as keeping you're engine cooler ?

OK, so the real issue is why is your jeep overheating...
well, we need to perform some tests.
1) Is it really overheating? I mean, the gauge could be wrong, the sender could be bad, or there could be some other electrical malady.
What evidence do you have to indicate that it's overheading?
I purchased one of those no-contact IR thermometers at Radio Shack for $29 (on sale). It's invaluable for stuff like this...
2) A cooling system needs to be pressurized to prevent the coolant from boiling over. If you see boiling, then it could be that there is a leak in pressure in your cooling system. I've seen this happen on the cap for the overflow canister. There is a rubber gasket in the cap that gets deformed...the it no longer seals...Check that one out.
3) If you really do need additional cooling, try this experiment first.
turn on the heat full blast. The heater core is nothing more than a small radiator with an electric fan blowing across it. If the temperature goes down, then this means that you need additional cooling.
4) This is really difficult to do in today's cars that have sealed radiators...back in the olden days, you could open the radiator cap and observe the fluid. Foamy fluid indicated that there was a cracked head...
5) Fan clutch. You probably already check this, but it's worth mentioning. While cool, the fan should spin freely. When hot, it should be stiff. It's worth checking.
now for the obvious...
1) thermostat...is it stuck?
2) waterpump. Nothing is leaking out of the weep hole? (it's in the lower back right (drivers side) of the shaft...you can't see it, but there will be dampness if it's leaking..
3) extreme bend or angle in any of the hoses? That lower radiator hose is crammed in there so tight, it's possible for it to be pinched...

These are the things I can think of...
Find out if any of these will help...

Ed
web/gadget guru

I wouldn't say I saw a drop in engine temp from it. I wanted a remote filter kit and since I am in phoenix (where it is 110 right now) I added the cooler as well just for good measure.

210 is normal (5.9 JGC) for me, however I plan to mount 2 coolers in my jeep one for the oil and one for the trans.

I have 2 factory coolers (non were used for the engine oil) for the trans and for our v8s the second is/was for the power steering, however I think they are 2 small for the job at hand.

I plan on B&M coolers that are built more like factory coolers, they take rocks better dew to the hedder design.

The only problem I have right now is a place to put them. I was thinking about the steering skidplate but even tho the coolers are tuff I don't trust the factory skid to protect them...

I think your problem is a pluged Rad, or Fan not comming on, or a bad rad cap, here in VA it gets hot, not 100+ like some of you nuts but upper 90s, and it dips on the high side of 210 but nothing to make me pucker up about.

Are you useing middle grade gas? like you should

OK, so the real issue is why is your jeep overheating...
well, we need to perform some tests.
1) Is it really overheating? I mean, the gauge could be wrong, the sender could be bad, or there could be some other electrical malady.
What evidence do you have to indicate that it's overheading?
I purchased one of those no-contact IR thermometers at Radio Shack for $29 (on sale). It's invaluable for stuff like this...
2) A cooling system needs to be pressurized to prevent the coolant from boiling over. If you see boiling, then it could be that there is a leak in pressure in your cooling system. I've seen this happen on the cap for the overflow canister. There is a rubber gasket in the cap that gets deformed...the it no longer seals...Check that one out.
3) If you really do need additional cooling, try this experiment first.
turn on the heat full blast. The heater core is nothing more than a small radiator with an electric fan blowing across it. If the temperature goes down, then this means that you need additional cooling.
4) This is really difficult to do in today's cars that have sealed radiators...back in the olden days, you could open the radiator cap and observe the fluid. Foamy fluid indicated that there was a cracked head...
5) Fan clutch. You probably already check this, but it's worth mentioning. While cool, the fan should spin freely. When hot, it should be stiff. It's worth checking.
now for the obvious...
1) thermostat...is it stuck?
2) waterpump. Nothing is leaking out of the weep hole? (it's in the lower back right (drivers side) of the shaft...you can't see it, but there will be dampness if it's leaking..
3) extreme bend or angle in any of the hoses? That lower radiator hose is crammed in there so tight, it's possible for it to be pinched...

These are the things I can think of...
Find out if any of these will help...

Ed
web/gadget guru


I have checked them all and none of them are the problem....

210 is normal (5.9 JGC) for me, however I plan to mount 2 coolers in my jeep one for the oil and one for the trans.

I have 2 factory coolers (non were used for the engine oil) for the trans and for our v8s the second is/was for the power steering, however I think they are 2 small for the job at hand.

I plan on B&M coolers that are built more like factory coolers, they take rocks better dew to the hedder design.

The only problem I have right now is a place to put them. I was thinking about the steering skidplate but even tho the coolers are tuff I don't trust the factory skid to protect them...

I think your problem is a pluged Rad, or Fan not comming on, or a bad rad cap, here in VA it gets hot, not 100+ like some of you nuts but upper 90s, and it dips on the high side of 210 but nothing to make me pucker up about.

Are you useing middle grade gas? like you should

My fan is belt driven and the clutch works perfectly, I do not have any boil over of the system at all..... I use cheap gas.....

I may have mistaken your engine, do you have a I6 or a 318?
If you have the I6 210 is still normal, figure this, the Stat is at 198 it opens at that number, i'm sure that the stat may not open at 198 on the button or even that the guage in the Jeep is right on the money.

I know that with a 318 they want you to use mid grade gas, with the 360 I have to use 92+, that kinda sucks but it's all good because it's quick.

I may have mistaken your engine, do you have a I6 or a 318?
If you have the I6 210 is still normal, figure this, the Stat is at 198 it opens at that number, i'm sure that the stat may not open at 198 on the button or even that the guage in the Jeep is right on the money.

I know that with a 318 they want you to use mid grade gas, with the 360 I have to use 92+, that kinda sucks but it's all good because it's quick.


I have a 318 and I have tried all the thermostats, 165, 180, 196 it still runs at 210 on the highway but my problem is at idle.... It gets very hot if I am not moving....

If it is getting too hot when you are idling or not moving as you say,it sounds like an airflow problem.As I am sure you know,when you are moving,air is forced through the radiator so the fan really only helps at idle.Are you sure that the fan clutch is ok?I know you said its new but new doesnt guarantee its good.This might sound stupid but I have to ask,is the fan shroud ok?You said its a new radiator so I assume there isn't a bunch of leaves and crap blocking airflow.I really doubt that you have a t-stat or water pump problem because that would probably be worse the faster you went.Whoever told you an auxilliary fan might help is probably right,but that is fixing the symptom,not the real cause of it overheating.I have a 96 ZJ with a 5.2 and it was around 95 today.It stayed at 210 like it always does and when I was stuck in traffic it barely went past 210.I have never had any issues and I have 123000 on it.

[QUOTE=xj31]If it is getting too hot when you are idling or not moving as you say,it sounds like an airflow problem.As I am sure you know,when you are moving,air is forced through the radiator so the fan really only helps at idle.Are you sure that the fan clutch is ok?I know you said its new but new doesnt guarantee its good.This might sound stupid but I have to ask,is the fan shroud ok?You said its a new radiator so I assume there isn't a bunch of leaves and crap blocking airflow.I really doubt that you have a t-stat or water pump problem because that would probably be worse the faster you went.Whoever told you an auxilliary fan might help is probably right,but that is fixing the symptom,not the real cause of it overheating.I have a 96 ZJ with a 5.2 and it was around 95 today.It stayed at 210 like it always does and when I was stuck in traffic it barely went past 210.I have never had any issues and I have 123000 on it.

Well I have had the fan clutch tested by several pros and they all say it works fine but they admit it has an airflow problem due to some other malody. No one can pin point the issue. Its a tough one but the person I bought the jeep from owned it for many, many years and they said it always ran hot. Thats why they replaced all the cooling system parts.. The jeep has 187,000 miles and other than the overheating problem every thing else works great. I only paid 2,500.00 for it and it has cold A/C and is 4 x4 . They had just replaced all of the cooling system parts, transmission and tires when
I bought it... All of their receipts total about what I paid for it....

It may has a clocked block or something.. I heard that there was a way to test the water flow from one side of the block to the other to see if their is an obstruction but I havn't found a mechanic that has the proper equipment for that....

Another thing is the water pump, I know that my 360 eats them, if yours is "tired" it may only be moving enough water at higher RPMs?! I did not know that 318s have belt driven fans, I thought that all the V8s had the 12V fan.

xj31 It was kinda cool to see your little ISP thing, however the dork part is lame, I love my Ghost Surf..