... and I'll be driving in the desert, New Mexico area, while on the trip. Does anyone run straight 40W oil in their KJ? I'm do for and oil change and differential oil change, and was thinking about using 40W in the engine. Manual just says 5W-30, but was thinking the pure 40W would be better for a road trip in the desert.

Thanks!

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2005 Liberty Sport, Full Skid Plates, Front and Rear Tow Hooks, Hella 500 Fogs, Yokohama Geolandars AT/S 235/70 16.
Julian, California

I would use 10w-30 when its hot outside. If you are going to be in the desert, then I take it that it will be hot...

Be sure to use a good air filter while you are out there. Wix is a good filter along with the new Amsoil filter. I would think twice about using a K&N if you are driving in alot of dust. Idk what filter you are using though..

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LOST KJ'S
Where are you going???
Current Jeep: 2004 Jeep Liberty
-Atlantic Blue
-Air Ride Rear Suspension ; OME/Rustys Lift ; Powertrax Locker ; Moog Lower Ball-Joints ; 245/70/16 Yokohama Geolander A/T-S's on MOABS ; Flowmaster 50 SUV
Lost #007082
http://www.cardomain.com/id/jeepjeepster

Depending where you are going in NM, it may not be as hot as you think. Current temps around Las Cruces/El Paso are aroound 90 during the day and 60 at night. You should be fine with the standard fill unless you expect to running hevily loaded.
I lived in EL Paso for 5 years, other than dust never had an issue with heat in any of my vehicles. Are you running the factory aribox? IF not get a prefilter.

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Frank
'05 Beryl Green Renegade 4x4 (of course)
LOST # FH050887

http://www.cardomain.com/ride/2122009

Weren't there reports of oil pump failures when people started using thicker weight oils? I can't remember where I read it - but I am pretty sure it was in regards to the Liberty and the 3.7L engine.

Stick with a 10w-30. There is no need for a thicker oil (especially if you run synthetic)

_________________
02 Liberty Limited
Silver Outside & Taupe Inside
Heated Seats, Sunroof & Infinity speakers
USA Spec I-Pod adaptor, Mopar Sub, Garmin GPS
Tow Package, Select-Trac
Rock Rails, Tow Hooks

I live in the desert. Summer temps are usually 100F + aroud here.
I run Amsoil 5W-30 and have never had an issue with heat.

I'd stick with the 5W-30 or 10W-30.

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Take the road less traveled.

Ditto. Two KJ's, both on Amsoil ASL 5W-30 in the High Desert heat and no problems. Good, Full synthetic, oils are engineered for high temps and they work just fine. Viscosity is not the only consideration when discussing oil properties vs. heat exposure.

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99 TJ
71 C101
04 KJ
03 SFA KJ Sport
LOST JEEPS So-Cal

Also - pressure is a measure of a resistance. The higher the pressure, the greater the energy spent moving oil around within the engine..

_________________
02 Liberty Limited
Silver Outside & Taupe Inside
Heated Seats, Sunroof & Infinity speakers
USA Spec I-Pod adaptor, Mopar Sub, Garmin GPS
Tow Package, Select-Trac
Rock Rails, Tow Hooks

Yep,that's why most new cars use 5w-20 oil,the '07 KJ's due I believe.

Thanks everyone, I'll go with the 10W-30.

_________________
2005 Liberty Sport, Full Skid Plates, Front and Rear Tow Hooks, Hella 500 Fogs, Yokohama Geolandars AT/S 235/70 16.
Julian, California