A friend of mine recently acquired a 2004 Wrangler with the 4 liter 6 cylinder engine. This engine has 270,000 miles on it. I believe suggested oil is 10w30. With this many miles would 10w30 still be the best oil? Climate is central NY where temps range from well below zero to mid 90s. This vehicle will be used occasionally and not driven hard. He plans on changing AT fluid, T case and diffs also. Engine leaks oil and plans are in place to replace oil pan, valve cover and rear main seals. Thanks for any suggestions.
2004 Jeep Wrangler high mileage oil suggestion
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No need to change now if it runs well and does not burn much oil.
Just use a good oil and filter and change it on some reasonable schedule.
Don't forget the cooling system. I'd really get after cleaning out everything and taking a good look at the radiator, hoses, clamps and the heater core and especially changing the thermostat.
Just use a good oil and filter and change it on some reasonable schedule.
Don't forget the cooling system. I'd really get after cleaning out everything and taking a good look at the radiator, hoses, clamps and the heater core and especially changing the thermostat.
Biggest question I would have is-how is the hot oil pressure, in drive? It's low on the '98 XJ 4.0 in my sig, drops to around 15 (which isn't horribly low) with 5W30 full synthetic, I've considered bumping it up to 10W40 in summer to try to raise it a little, since it starts instantly even when 0F.
Don't see many tj's with that kind of milage.many are weekend toys and have very low mileages
The spec oil is indeed 10w30, with 5w30 allowed for the colder months.
My top recommendation would be Pennzoil High Mileage for it.
My top recommendation would be Pennzoil High Mileage for it.
230,000 Central NY miles means that frame has to be almost toast.
Anyway, my 4.0L was happy on the super cold morning with semi synthetic 10w-30.
Anyway, my 4.0L was happy on the super cold morning with semi synthetic 10w-30.
You could use 10W30 HDEO. If your friend insists on a PCMO 10W30 PHM would be my choice.
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Originally Posted By: bullwinkle
Biggest question I would have is-how is the hot oil pressure, in drive? It's low on the '98 XJ 4.0 in my sig, drops to around 15 (which isn't horribly low) with 5W30 full synthetic, I've considered bumping it up to 10W40 in summer to try to raise it a little, since it starts instantly even when 0F.
Sure keep that oil filter in bypass mode who needs it.
Biggest question I would have is-how is the hot oil pressure, in drive? It's low on the '98 XJ 4.0 in my sig, drops to around 15 (which isn't horribly low) with 5W30 full synthetic, I've considered bumping it up to 10W40 in summer to try to raise it a little, since it starts instantly even when 0F.
Sure keep that oil filter in bypass mode who needs it.
15PSI hot idle is within spec
Tell him he is a brave soul to buy a Jeep with 270k on it....10w30 PYB and fix the leaks.
I'd use PYB 5W30 in the winter and probably PYB 10W30 in the summer and see how that goes. I'd hold off on the 10W40 and use it only if I had some kind of issues with the 30 grade oil.
As far as his other plans, they sound good.
As far as his other plans, they sound good.
Originally Posted By: demarpaint
I'd use PYB 5W30 in the winter and probably PYB 10W30 in the summer and see how that goes. I'd hold off on the 10W40 and use it only if I had some kind of issues with the 30 grade oil.
As far as his other plans, they sound good.
40 and 50 grade oils seem to make the 4.0 get a bit of top end noise.
I'd use PYB 5W30 in the winter and probably PYB 10W30 in the summer and see how that goes. I'd hold off on the 10W40 and use it only if I had some kind of issues with the 30 grade oil.
As far as his other plans, they sound good.
40 and 50 grade oils seem to make the 4.0 get a bit of top end noise.
I suggest Pennzoil High Mileage or Valvoline MaxLife SynBlend. I would run 5W-30 during winter & 10W-40 the rest of the year.
+1 on that ...
Originally Posted By: Miller88
Originally Posted By: demarpaint
I'd use PYB 5W30 in the winter and probably PYB 10W30 in the summer and see how that goes. I'd hold off on the 10W40 and use it only if I had some kind of issues with the 30 grade oil.
As far as his other plans, they sound good.
40 and 50 grade oils seem to make the 4.0 get a bit of top end noise.
I recall someone else mentioning that to me. I think the 5W30 winter, 10W30 summer oil recommendations would be worth a try if the engine is running well and the OP addresses the leaks. The truth is 5W30 should work all year, but the 10W30 might be a bit more shear resistant.
Originally Posted By: demarpaint
I'd use PYB 5W30 in the winter and probably PYB 10W30 in the summer and see how that goes. I'd hold off on the 10W40 and use it only if I had some kind of issues with the 30 grade oil.
As far as his other plans, they sound good.
40 and 50 grade oils seem to make the 4.0 get a bit of top end noise.
I recall someone else mentioning that to me. I think the 5W30 winter, 10W30 summer oil recommendations would be worth a try if the engine is running well and the OP addresses the leaks. The truth is 5W30 should work all year, but the 10W30 might be a bit more shear resistant.
Originally Posted By: dlundblad
My next oil change is going to get a jug of 10w40 PYB, but I am going to water it down with a quart of 5w20 PYB to make a thick 30 weight.
If he insists on a 10w30, Pennzoil HM is about as thick as you can go in 10w30.
I have used that exact blend in the past, it worked well. Good plan.
My next oil change is going to get a jug of 10w40 PYB, but I am going to water it down with a quart of 5w20 PYB to make a thick 30 weight.
If he insists on a 10w30, Pennzoil HM is about as thick as you can go in 10w30.
I have used that exact blend in the past, it worked well. Good plan.
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