I have a 98 Jeep Cherokee that I just purchased (95k miles). It has the 4.0 inline 6 cylinder motor. It did not come with an owner's manual and the oil grade is not printed on the oil cap. What grade of oil is spec'd for this vehicle? Any reason I can't run 5w/30 year round? For the record, I purchased it from my employer. It was a fleet vehicle. To give you an example of usage, it has only logged about 650 miles since they changed the oil on April 4th. The vehicle was driven primarily on campus. The maintenance shop was using Mobil 10W/30 conventional.
98 Jeep Cherokee, what oil is spec'd?
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Sis had a '99 which specced 5W-30. I suspect yours is the same.
Which 4WD system does it have? SelecTrac has the "FULL TIME" and "PART TIME" selections where the CommandTrac has "4WD LO" and '4WD HI" selections.
Trans takes old, basic Dex/Merc as does the transfer case.
Unscrew the trans drain plug and exactly one gallon would come out.
Which 4WD system does it have? SelecTrac has the "FULL TIME" and "PART TIME" selections where the CommandTrac has "4WD LO" and '4WD HI" selections.
Trans takes old, basic Dex/Merc as does the transfer case.
Unscrew the trans drain plug and exactly one gallon would come out.
Here comes the 5W vs 10W argument, or the -30 vs -40 argument, or the PCMO vs HDEO argument.
...or all 3
...or all 3
The owners manual says 10w30 down to 0F and 5w30 below that.
Whipcitywrencher
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I'd go 5w30 year round.
There is no reason you can not use 5W30 all year.
If it was my vehicle, I would use PYB 5W-30.
Only 650 miles on last oil change, but how much idling?
Only 650 miles on last oil change, but how much idling?
What do you use in your other vehicles ? I would be tempted to use the same , if you are satisfied with it .
I'd run a good 5W30 in it.
Originally Posted by Chris142
The owners manual says 10w30 down to 0F and 5w30 below that.
This is the correct answer...
The owners manual says 10w30 down to 0F and 5w30 below that.
This is the correct answer...
My van gets full synthetic 20W. 5w/20 currently, Ow/20 on the next oci. My other vehicles get 5W30 HM. Currently, I have 6 jugs of Havoline HM 5w/30 that was purchased for less than $2/qt. So, will probably run that when I change the oil.
Mine has the Command Trac with 4Hi and 4Lo. The vehicle was pretty much start and go on campus. Not a lot of idling.
Originally Posted by Chris142
The owners manual says 10w30 down to 0F and 5w30 below that.
Beat me to it, that's what my XJ owners manual says. But you can run anything, mine goes through 5W30 like water, it seems to like ML 10W40 and random 15W40 HDEOs the best.
The owners manual says 10w30 down to 0F and 5w30 below that.
Beat me to it, that's what my XJ owners manual says. But you can run anything, mine goes through 5W30 like water, it seems to like ML 10W40 and random 15W40 HDEOs the best.
That engine will run fine on anything from Supertech 5w30 to a HDEO 15w40. I've personally had the best UOAs on my 4.0L using Pennzoil conventional 5w30 and 10w30.
Originally Posted by Chris142
The owners manual says 10w30 down to 0F and 5w30 below that.
Yes, but odd that the manual shows that 5W-30 is only good to 60F. I would argue with that.
5W-30 in my 98 4.0L now.
The owners manual says 10w30 down to 0F and 5w30 below that.
Yes, but odd that the manual shows that 5W-30 is only good to 60F. I would argue with that.
5W-30 in my 98 4.0L now.
Originally Posted by ammolab
Originally Posted by Chris142
The owners manual says 10w30 down to 0F and 5w30 below that.
Yes, but odd that the manual shows that 5W-30 is only good to 60F. I would argue with that.
5W-30 in my 98 4.0L now.
The 4.0 is an old, somewhat loose AMC design-I'm sure the CAFE gang would like you to run a nice thin oil in it, but mine used a lot of 5W30, even in winter, when I first got it. It's also (somewhat) quieter when starting with Valvoline MaxLife (NextGen) 10W40, and has no issues getting started & developing oil pressure with it either. I'm sure 235,000 mile old bearings & rings are helping with that somewhat...
Originally Posted by Chris142
The owners manual says 10w30 down to 0F and 5w30 below that.
Yes, but odd that the manual shows that 5W-30 is only good to 60F. I would argue with that.
5W-30 in my 98 4.0L now.
The 4.0 is an old, somewhat loose AMC design-I'm sure the CAFE gang would like you to run a nice thin oil in it, but mine used a lot of 5W30, even in winter, when I first got it. It's also (somewhat) quieter when starting with Valvoline MaxLife (NextGen) 10W40, and has no issues getting started & developing oil pressure with it either. I'm sure 235,000 mile old bearings & rings are helping with that somewhat...
I've been running 10w30 in my dad's 94 XJ 4.0 for the longest time. No issues. I'm in a hot climate btw.
Current change is ST Syn 10w30.
Current change is ST Syn 10w30.
had a rubicon that called for 5w30. It got 5w or 15w40 season depending...backed by UOAs
Im running Valvoline maxlife HDEO 15W40 in my jeep in S.FL. Reason I run it? Its an HDEO and is cheap ($15 per 5 quarts) since it really never gets below 40s here no issues.
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Originally Posted by bullwinkle
Originally Posted by ammolab
Originally Posted by Chris142
The owners manual says 10w30 down to 0F and 5w30 below that.
Yes, but odd that the manual shows that 5W-30 is only good to 60F. I would argue with that.
5W-30 in my 98 4.0L now.
The 4.0 is an old, somewhat loose AMC design-I'm sure the CAFE gang would like you to run a nice thin oil in it, but mine used a lot of 5W30, even in winter, when I first got it. It's also (somewhat) quieter when starting with Valvoline MaxLife (NextGen) 10W40, and has no issues getting started & developing oil pressure with it either. I'm sure 235,000 mile old bearings & rings are helping with that somewhat...
CAFE has not a thing to do with the grade. AMC recommended 10W30 if the owner used a multigrade above 0F and a 20W20 if the owner was using a single grade. This was in 1968 when CAFE was not even a figment of anyone's imagination.
Originally Posted by ammolab
Originally Posted by Chris142
The owners manual says 10w30 down to 0F and 5w30 below that.
Yes, but odd that the manual shows that 5W-30 is only good to 60F. I would argue with that.
5W-30 in my 98 4.0L now.
The 4.0 is an old, somewhat loose AMC design-I'm sure the CAFE gang would like you to run a nice thin oil in it, but mine used a lot of 5W30, even in winter, when I first got it. It's also (somewhat) quieter when starting with Valvoline MaxLife (NextGen) 10W40, and has no issues getting started & developing oil pressure with it either. I'm sure 235,000 mile old bearings & rings are helping with that somewhat...
CAFE has not a thing to do with the grade. AMC recommended 10W30 if the owner used a multigrade above 0F and a 20W20 if the owner was using a single grade. This was in 1968 when CAFE was not even a figment of anyone's imagination.
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