RPM3DINC

I have 4:10 Gears and BamaChips 93 Race Tune in, and in Drive (OverDrive Off), at 70MPH it runs at 3,500 - 3,800 RPM's, will that hurt the engine if I run it at that constant RPM range?

Torch_Vert

It won't hurt it immediately, but it will increase the rate of any normal wear (i.e. instead of getting 150K out of the engine, you might get 120K)

You should also consider this "severe usage" and adjust your oil change schedule accordingly.

It's obviously going to affect your wallet if you do a ton of highway driving.

RPM3DINC

OK, I was just curious, I can turn the OverDrive back on with the Auto-button, that is not a problem... I mainly use "DRIVE" to pass people and then put it back into overdrive once I am past them... but sometimes I like to listen to the engine scream down the road too, just wanted to make sure I wasn't KILLING the car...

TotoGT06

Im the exact same way, its easy on the engine with OD on when going down the freeway, but when you want to show off and pass someone, turning that OD off is great. I only turn it off when passing someone i think would like it, other than that I leave OD on

lundefinedl

It depends on the engine. I've had some 4 bangers that would run at 4k at 80 mph and those engines lasted forever. One nice thing to consider about our 4.0L engine is that the stroke is pretty short for the displacement, so the average speed that the piston is moving is lower.

Sancho805

i also turn OD off when i'm passing up cars on the freeway or feel a need for some quick acceleration .... ur good as long as you dont ALWAYS run it hard. i admit, it sure is A LOT more fun with OD off in an auto