2004 Wrangler 4.0L

[2004TJ]

About 300 miles ago I changed my oil and decided to put Royal Purple in. Now I'm wishing I would've just put in Castrol Syntec Blend which is what I originally set out for (someone convinced me to try RP). You think it would be ok to drain that stuff out, and go ahead and do the Castrol now? or should I just wait until my 3,000 miles is up (I change every 3,000 I don't care whats in it).

 

[HawkeyeScott]

It would hurt nothing to do either. IMO, you'd be wasting some high-end oil by drainig RP after 300 miles. I'm sure the oil will protect just fine. Can I ask what the Jeep is doing that's making you want to drain the RP so quickly?

I would wait and use the RP for at least 3K. But if you have too much money/oil, perhaps you should go ahead and change it out.

 

[artificialist]

Leave the RP in if it is the correct viscosity. Sure, other oils outperform it, but RP is just fine.

One great thing about RP is that it has more anti-wear additives than SM oil. That is good news for you since no Jeep 4.0 has roller lifters.

 

[2004TJ]

I have several people who know alot about oil tell me I should go with something else, namely Castrol. I'm planning on keeping this Jeep for as long as it'll run so I really want to put something good in it.

 

[Gary Allan]

Leave the RP until you've gotten your money's worth out of it. You will be planting daisies before you destroy a 4.0 with maple sap as an lubricant. I've run everything from 0w-10 to 5w-40 in mine. Do UOA if you want to be sure that you're going to get 350k instead of 300k out of it.

Keep your fuel system clean.

 

[2004TJ]

now I'm hearing that Valvoline is the best.......[censored] HELP ME!!!!!!!

 

[mikeg5]

haha dude.. find a synthetic on SALE or just use Pennzoil, havoline or any good named brand of oil and please leave it at that. that motor is the LEAST of your worries.. is this jeep an auto?? if so , that should be priority not your indestructable motor. i have had 2 jeeps in the past. my wrangler had almost 200k miles on her before i traded it in. i threw in whatever i wanted as far as oil goes and she ran fine and hard. tips for you

keep your intake clean
keep your atf (if an auto) clean

thats it. dont worry about the motor, she will run on dog pizz

 

[2004TJ]

thx bro....I have the 5 speed. You're right I shouldn't stress too much I guess

 

[Greaser]

Go to the used oil analysis forum and type in Jeep 4.0L.Make up your own mind by doing a little reading in that section.

 

[Eddie]

My 1995 JGC 4.0 was changed to Mi 10w30 at the first 1,500 mile oil changed and stayed with the Mobil 1 10w30 & PureOne oil filters till I sold it at 197,000. Still running great and never a valve cover off. Two rear main seals were changed. OCI was 6,000 miles. Today I would run Mobil 1 5w30 or 5w40 or Pennzoil 5w30 and do a 7,000 mile OCI if backed up with a used oil analysis at ~ 14,000 miles. M1 & PP are easly availiable at WalMarts for ~ $ 22.98 & $19.98 respectivly for a 5 quart jug. Both great oils without the hassle of mail order or higher priced options which have demonstrated no better used oil analysis on this engine.