Hey guys so after driving down from Seattle and putting about. 2k miles on my car the check engine just flashed like 4-6 times! People drive really fast in So Cal literally 80-100 mph is the cruising speed. While following my friend in her e350 and trying to keep up, I shift really slow, the car did its usual jerking at like 2500rpm in 3rd! My brother says I have been lugging it but for fear of transfer case problems I shift at low rpm often. So as it was jerking the chk engine flashed I got in the freeway and it went away! Quite freaked out, sorry I can't describe it better but I'm super tired!!! Any help is greatly appreciated!!! Nick

 

"the car did its usual jerking at like 2500rpm in 3rd"? If by that you mean it was jerking from being in too high of a gear for the speed then you are in way too high of a gear. If you upshifted so much that the car was on the verge of stalling maybe that is why your check engine light came on momentarily.

If you are doing that to save the transfer case, I don't know that is such a good idea. Nothing wrong with upshifting early to try and improve your MPG or for smoother shifting or whatever your reason. But if you are getting into such a high gear that your engine is lugging that doesn't seem very safe if you need to be accelerating onto a freeway. I would think if there would even be any value to prolonging the life of your transfer case it would be minimal at best compared to just driving sensibly on a daily basis and changing the fluid regularly.

If I am nit looking to zip away from a traffic light I often skip shift (1 to 3, 3-5) at about 2500-3000 RPMs or so. The engine has enough torque that you can accelerate cleanly and smoothly and not cause the engine to lug and for you to be a source of frustration to drivers behind you.