Oil Type


#1

I just purchased a 2002 Jeep Grand Cherkoee

it has the 4.0 Straight Six Engine

it has 80,000 miles and is very clean and according to maintance records well kept

A) Would a change to synthetic oil work

B) Is it worth the price differance to use the synthetic


#2

i myself and not a fan of synthetic oil, yet with such an old car i would use it


#3

Ask yourself: What got it this far? Keep on keeping on! 80,000 miles now is not much to get excited about. Come back when you have 200,000 miles. Even then, use what has worked for you.


#4

FWIW, the mobil website gives range of recommendations (conventional and synthetic):

http://www.mobil1.com/usa-english/motoroil/car_care/which_oil/WhichOilOption2.aspx


#5

Wal-Mart has lowered the price of Castrol Syntec to less than $20 for a five quart container, so I bought one. The price difference doesn’t count for anthing. It’s more a measure of how cheap a person wants to be. I want to be cheap, but 3,000 miles on ten extra dollars doesn’t seem like much. Castrol had a great infomercial years ago about their Syntec. Their normal oil is good enough though. If your engine has roller lifters and a timing chain, you might get a little more benefit from synthetic. From my experience, and most people’s experience: I have to wonder myself , how I would know the difference between oils.


#6

The 4.0 is a tough old beast, you could run it with cooking oil and pig snot and it’d go another 100k miles.


#7

I agree with Josh. That’s the old American Motors (Rambler) Six. It is not a lubricant critical engine. Anything labeled “Motor Oil” will work just fine.


#8

Unless the manufacturer recommended synthetic, it does not “need” it.

That said synthetic is a better oil, but what will you gain? Well assuming the body holds up and you don’t get in a serious wreck etc. and that the engine does not suffer a non-oil related failure first (not many engines get this far) then it might mean a little longer life, maybe a few thousand miles.

The synthetic will also mean a little better mileage, but it is likely to be less than you can measure.

I like synthetic, but I doubt if I would bother.


#9

From my experience, and most people’s experience: I have to wonder myself , how I would know the difference between oils.

Great comment. This is my experience as well.


#10

2002 with 80k is an old car? My DD is an 86:)

I would not spend the money on synthetic though.


#11

from what i have been reading it is not worth switching in older cars.

once the car has been run with regular oil, just keep using it.

if you start a car on synthetic oil, then it is worth continuing with synthetic.


#12

Wal-Mart has lowered the price of Castrol Syntec to less than $20 for a five quart container

BJ’s has Mobil-1 6 quart case for $23. Just bought a case yesterday.


#13

I know there is a point of mileage and age when changing to synthetic oil can cause oil leaks. I think you might be at or about at that point. IMHO, I would stick with your regular oil change intervals using a good recommended oil.

If you had 50K or less, I might consider changing to synthetic. They have much greater and consistant qualities that can double or even triple your oil change intervals. If you do change, talk to an amsoil representative. Of course, he wants to sell you the oil, but most can advise on the mileage age issue and possible leaks from changing.

Good luck


#14

Well, synthetic oil does not “cause leaks,” however it may cause existing leaks to be worse (simply because it is thinner and may remove some of the existing sludge). Of course, the correct solution is to fix all the leaks, regardless of the oil type.

IMHO, synthetics really have two advantages over conventional oils. They offer better cold start lubrication (somewhat reducing wear), and they provide an opportunity to extend you oil change intervals (within reason). Personally, I would not exceed the manufacturers recommended oil change interval without an oil analysis to show I was still OK (both in terms of the oils condition and the level of contaminates).


#15

I’m not to sure about the snot, but any oil meeting current specs and the proper viscosity for the climate will likely do fine in a Jeep 4.0 if serviced regularly. It is an anvil of an engine. I have owned 5 and serviced and repaired many over the years. Only a 4.9 Ford might possibly out distance that engine.


#16

Such an old car? It’s a 2002! I bet you think cars made in the 90s are classics…


#17

its not an old car, yet 80k isnt exactly new, switch to synthetic


#18

its not an old car, yet 80k isnt exactly new, switch to synthetic