Motor oil

[jeeprs]

Hey guys I just got a 88 Grand Wagoneer and was wondering what oil you use or recommend. Conventional/ synthetic? It's got 122k miles on it.Thanks

[wiley-moeracing]

Any oil you can find will work fine, save some money and go regular oil.

[devildog80]

x2 on the dead dinosaurs, and in AL I would use 10-40, as you probably never drive it enough to get the benefit from the synthetic.

[backroadin']

I run regular rotella 15-40, but the motor is rebuilt and has aftermarket cam, so I do it for the extra zinc. For yours, what willey-mo said.
You can run the high mileage oil - it's usually no more expensive.
And Walmart brand oil is actually not bad..... just sayin

['89_Wagon]

I've thrown rotella, wally world oil, and Yamalube at my high mileage motor. No difference with any of them. I needed a little bit of the Yamalube for another machine and didn't feel like going out to the store.... so in the Jeep it went!

[jeeprs]

Thanks for the info guys

[Crankyolman]

After my cam went bad leading to an engine rebuild I did a ton of research on oil. Oil companies continue to change their formulas and continue to remove the things needed by non roller cams. This is true of diesel oils too.

Now, granted my engine is older (1972) but my understanding is they never changed the cam to roller so it still needs the zinc.

After all that research I started using Lucas Hot Rod oil because it has the highest zinc of any of them. You could run 50% HRO and 50% regular oil and still have more than most including rotella. The only real problem is this may cause eventual clogging of the cataly converter but personally I'd rather change that than the engine.

[sierrablue]

Originally Posted by devildog80

x2 on the dead dinosaurs, and in AL I would use 10-40, as you probably never drive it enough to get the benefit from the synthetic.

x2 on the 10W-40. More zinc = more engine life, pretty much whenever you don't have a roller cam and/or lifters. The reason I don't go synthetic is that it leaks; no point in flushing money into a fluid that goes through a quart every week and a half or so...

[Cliff]

I use Brad Penn oil because of the zinc. I had used it in a drag racing AMC Spirit with a 401, and it made sense to use it in the Jeep too.

[rang-a-stang]

The bigger comment: DO NOT USE CRAPPY OIL FILTERS!!! I used a Fram on my 401 break-in and my engine sucked the filter element up like a straw. I had always run cheapie Fram and generic oil filters and thought people were being dramatic when they hated on cheapie filters. Never again.

Run WIX or Baldwin. I read all over the AMCForum and those guys all swear by the Baldwin B8. I am not sure what year needs a metric filter so research that (B8 is NOT metric and 88 MIGHT be the first year of metric filters...).

[Brynjminjones]

I use 10w40 here too. Just regular Valvoline MaxLife for me.

Mine has a rebuilt motor with about 10,000 miles on it. I used 20w50 for a while, but it seemed too thick when cold and I could hear that oil wasn't circulating as quickly as I'd like.

With 10w40 it builds oil pressure nice and quickly on startup, but keeps high enough pressure at hot idle after a high speed run.

I also changed the oil filter adapter to take the Mopar 090 filter, as used by Jeeps with the 4.0.
I've always found it to be a good filter, plus I like only having one type of filter for all our Jeeps!

[nograin]

Depends how worn it is and how hot it runs.
10W-30 should be fine but if you see the oil runs hot, or that the engine seems to be eating oil, then try 10W-40. My last 360 was pretty worn and was getting the previous generation of Rotella 5W-40 synthetic T6. The lower W grade is a little easier on the engine when cold. If you aren't in a cold climate or not doing a lot of short runs, then its not so important.



if you want to get into the ZDDP game, look for an oil with at least 600 and no more than 1400 ppm. Valve spring pressures on a stock 360 cam are not anywhere in the range where one should be sweating this.