artpics

so went into the sierras this week for some skiing in mammoth. but on the main climb 4000ft to 7000ft over 8 miles the jeep wanted to be at 4000rpm@60mph for about 5miles this is a 2dr rubi with 35s, superchips running on 91 octane

main question are these revs safe on the engine or should i have slowed to 40mph and let the semis catch me

wayoflife

i don't know, the 3.8L likes to rev high and seems to perform well at that range. i'm sure you were fine.

JayhawkJeep

My thoughts are that engines are designed to run. That for the most part a load on the engine is not a bad thing. As long as you are not in the red you should be fine (until you run out of gas)

artpics

Great thanks i hate that sherwin grade - i also took the old road at paradise (swall meadows the one with 69 bends) with my new lower control arms i had no esp issues and Coyote Flats gave me some nice memories.

wayoflife

nice! glad to hear your control arms and the additional caster you have helped out

sburggsx

I haven't tried this in my JK yet, but I learned something from driving motor homes. I can either do 55-65mph tached out and drinking fuel... OR... I can do 40-50 at about 1500 rpms less. It took a while to learn and maybe it has to do with getting older... but it sure seems to me to be a lot easier on the equipment. In the end I'm sure the mini-van motor will probably hold together but do you really want to wind it out for that long for non-off road reasons?

horwitzs

If the motor was going to blow up at that RPM, then they would have made 4k beyond the redline.
Sure, the motor will wear faster if you drive it like that all the time, but for an occassional climb where you need the extra HP, no biggie.

rozzman10

i pulled a 16ft trailer with two four wheelers for 5 hours to the mountains across tennessee.. some of the hills i would climb the motor would go to 5500 ( red line ) and stay there until the top of the hill.. YES the motor will be fine at that rpm.. given you are moving along and keepin the hot air off the motor.. and that you dont stay there CONSTANTLY.. just watch the temp

rhino4bs@yahoo.com

i hold mine at 5500 for 10 miles still runs lifetime warranty

spinlock

Check out this video of a JK going up a mountain road in CO with the RPM pegged all the way:

http://www.youtube.com/watch?v=XNo_Sr71pls

I have the lifetime warranty too, but the last thing I want to do is to get a new engine and have to go through the maturing process of the PCM.