What kind of oil should I use for a 98 Jeep Grand Cherokee ?

[Candymancan]

I'm going to change the oil in my mom's Jeep this will be my first time ever changing oil in a car, but it doesnt sound hard. Just warm the car up, turn it off and unplug the oil bolt on the pan and have it drain into the container to catch the oil. Then let it drip until its all gone, take out the old oil filter, and replace it with a new one after oiling the seal's around the filter. Then fill it back up, check the oil level run the engine for a little and check the oil level again.

(Ive seen video's that say to drive the jeep on a ramp however i can fit under the Jeep just fine, is this ramp to tilt the car upwards so all the oil will drain out ? If so cant i just park the Jeep on a slightetly tilted hill so the front is up higher then the back ?)

Ok so i get that, but what im wondering is what kind of Oil should i buy for a Jeep Grand Cherokee Inline 6 4.0 with 160k Miles ? Ive asked my mom what kind of oil she put in the car when it was last changed but she doesnt know only that it was high mileage oil. I suspect it was some kind of generic high mileage oil because the oil change only costed her $20. She also doesnt know how many miles its been since she changed it i suspect around 3-5k miles. I checked the oil on the dipstick and its pretty much dark brown/black color so i think it needs changed.

The manual says to get 10w30 multi-viscosity oil, but there are so many brands..

 

[SUPERD]

no need for ramps, they are just for access to the pan on a car, another awesome thing about jeeps, you can actually work under most of them.
everyone is gonna tell you their brand is better than yours, I like castrol, use what ever you want, just not generic or reclaimed!
stick with whatever you choose though, changing brands frequently can cause issues in higher mileage vehicles, don't use synthetic either, stick with fossil oils, switching to synthetics in an older worn engine can cause all sorts of problems from leaks to engine failure. also use a name brand filter, not a parts store cheapie, i've cut open many oil filters in my day, you would be surprised what some use for filter media, seen shredded newsprint in one off brand, cant go wrong with one from wix, hastings,or fram.

 

[Candymancan]

Fossil oil is Conventional right ? How much oil does the inline 6 need ? Oh and you mentioned you use castrol. Would this castrol GTX ? Should i get the high mileage oil or just normal Convntional Castrol GTX 10w30.

I suspect what is in the Jeep right now is Penzoil High mileage, i was reading online that Jiffylube uses nothing but penzoil. Thats where she usually gets her oil changes too

 

[AZ Outlaws]

....use a name brand filter, not a parts store cheapie, i've cut open many oil filters in my day, you would be surprised what some use for filter media, seen shredded newsprint in one off brand, cant go wrong with one from wix, hastings,or fram.

A few months ago I ran across a very comprehensive oil filter review but I can't find it now. I posted my question on the forum where I think the review was posted so I'm still waiting for a reply.

I agree with name brand filters, but even some of them like FRAM are no longer a top rated filter. If memory serves me right, Wix, Hastings, Purolator were some of the best filters the guy rated.

I'll update this if I can find the comparison review I'm looking for. BTW... there are several brands that are identical and made by the same maker. All oil filters are not created equal.

 

[Candymancan]

Ok i parked the car on a slight incline 10 degree's engine up the hill, i drove the car around to heat up the oil. I then unscrewd the oil plug and with cowhide gloves i unscrewd it the rest of the way and let the black oil drain into the pan. After about 5 minutes i unscrewd the oil filter and more oil came out so i let it drain for another 5 minutes.

I plugged the oil pan up and took the new filter oiling the seals with the new oil and screwd it on pretty snug. Filled up 6 quarts of the new oil ran the car for a few minutes, turned it off and checked the oil level and its perfect right in the middle of the full line.

The new oil i used was Vavoline Max life Synthetic Blend, the filter i got was a Purolator Pureone filter.

Oil pressure is still around 30psi idle and between 30-40 as i drive, so i guess thats normal i dunno, i coulda sworn it was always around 40psi idle or driving in the past. Aw well, at least i got rid of the nasty black oil in the Jeep.

 

[CT99XJ]

Purolators are good. I've always used Delco filters for a Ford E-van because they're a bit larger and let me fit an extra half quart. Usually add a quart of Marvel Mystery Oil every time, too.

 

[Chevy]

I have always only used Royal Purple in any of my vehicles