Best oil for 2001 jeep cherokee

Hey y'all I've been using pennzoil high mileage 10-30 on my jeep and it's made my jeep noisy, I was curious if there was a Better brand to use?

Whatever you use, make sure it's conventional, synthetic is the absolute worst for 4.0s. I use Wolfs Head 10-30, PA made and cheap. Substitute a quart with Marvel Mystery Oil and your motor will never run better.

I've heard that marvel stuff has blown motors. And also what about the synthetic blend? That's what advance auto recommended for my 96

I've heard that marvel stuff has blown motors. And also what about the synthetic blend? That's what advance auto recommended for my 96

Synthetic oil can cause seals to leak, especially on high milliage engines.

I have heard the same about using synthetic being used in high mileage engines when it has not been used before. No science behind it as I know.

When I bought mine the PO informed me that he had been running mobil one full synthetic 10w-30 since 90k and it's all I run in it. It's now got 180k on it. I've had people tell me synthetic is bad and people tell me conventional oil is bad lol. I may be wrong but I think that when it comes to oil it's really everyone's own personal preference. I've had good luck with full synthetic and conventional oil.

The synthetic oil is much thinner than conventional oil and will find the path of least resistance. If you start using synthetic at about 20-30,000 miles it's great. If you rebuild and use synthetic after break in period it is great. High milage engines are not the place to start using it.

As far as additives go, as many opinions as there are forum members, some love it and swear by it, others swear at it.

Well I'm just curious cause I bought the valvoline 10w-30 synthetic blend, half conventional half syn? I had the issue with synthetic, front seal, oil pan gasket, rear main, valve cover and oil filter adapter all leaked.

The reason why synethetic oil causes leaks is because its meant to clean sludge out of an engine whereas conventional oil doesnt do that. Conventional oil will let gunk build up around seals that have potential to leak, and most likely will leak down the road. It may happen that by the time this does occur the engine might be done, or it could happen while youre still driving the jeep.

Well I put syn in my 88 and after about 6 months all seals leaked.

I have been using Castrol GTX high mileage 10W-30 (green bottle) and so far I have had good luck with it.

I ended up going with valvoline 10-30

Marvel doesn't blow motors. Substituting a quart won't blow a 4.0, Or pretty much anything that doesn't have a pre existing problem. My dad's been using a quart of marvel n his oil changes for almost 40 years... Never had a motor blow.

Must be one of those things! Haha I will have to try that when I change my oil in the lifted jeep

i run Rotella 15-40 in my Heep and my 47...best oil you can put in 4.0. the zinc content is high in this oil and Zinc is good for the 4.0 and other older engine designs. 15-40 non syn maybe a little thick for some of you in the cold climates this time a year but again it is the best you can put in...you may have a 10w something in your areas which would be fine....Marvel is good stuff but it is not meant to be left in there for very long...it is for cleaning the engine and frees sticky lifters..500 miles is the most i would ever leave that stuff in there...
cameron

The Rotella you are using does it say it's for Diesel engines?

The Rotella you are using does it say it's for Diesel engines?

yep...conventional and T6 are for diesel engines...good stuff
Cameron

ck1 said:

yep...conventional and T6 are for diesel engines...good stuff Cameron

okay just makin sure I'm fixing to buy the right stuff for 4.0

yep...conventional and T6 are for diesel engines...good stuff
Cameron

That's why I run full synthetic Shell Rotella T-6. I have 189,000 miles and have been using this for the last 5 oil changes. Its diesel oil so it has high zinc and is made to withstand hard use and temperatures. Synthetic oil is not bad for a 4.0. It's simply "slicker" than a conventional oil and will make it past bad seals a lot faster than a conventional oil.

The 5-40 is great for winter as it's only a 5 weight oil at startup

I run Pennzoil 10/40 with a quart of Lucas...works real good...232000 miles