i think i might have a overdrive issue
 

at 65 mph im around 2300 rpm 2600 at 70 mph does this sound right for a overdrive dually trans?

What trans do you have. My 94 dually doesn't sound to far off from that and its a 5 speed.

not sure i just got the truck its a auto with overdrive

Its a 4l80e. It could have real low gears to.

sound about right i run right around 2400 at 70

ya the 4l80 overdrive is .80 i think and you probly have 4.10s mine is a lyyle higher than that 2500 at 65 and 2800 at 70

ya i have 4:10s

is 2500 rpm ok for these motors for a long trip i dont like going over 65 sounds like its going to blow lol

2500 rpm is fine on them.

its just going to suck fuel

what gear should i put in? i dont haul much but do a lot of freeway driving

Drive

mine gets 18 going 73 reving at 2800 from goodland to garden city so i think youll be fine

I ment gear ratio

sorry about that confusion. i got 3.42 gears and at 63 mph im turning 1800 rpms. its just in a dually that would be a pig around town and you couldnt tow much weight. i would probably throw a set of 3.73s to keep the towing weight up and that lower the rpms on the highway a bit

I just bought a 97 c3500 and I am running 2700 rpm's going 70. I thought my overdrive wasn't working either but I think we just have really low gears.