First let me say I'm glad to find a site like this and I'm exited to learn all I can. I just bought a '98 Dodge Ram 2500 with a 5.9 v8. It's got 112,000 miles and seems to run good. I like it alot and hope to mod it up. I do have one question about the trannys. I've heard alot of rederick about them so maybe I'm a little paranoid but I think mine might not be shifting from 3rd to 4rth. I say this because I don't know what the RPMs should be at 60 MPH. I don't think they should be at 2500 with stock 3.5 gears. Can anyone relate?

 

welcome to DF, when your tranny is at those rpms, is it in overdrive?

 

I would think that it would be. I didn't turn overdrive off with the switch. All I know is that my last cars cruised down the freeway at about 1700-2000 rpm so i wanted to ask truck owners what there trucks were doing.

 

Welcome aboard !!

I recently had a problem with my tranny slipping in and out of overdrive, and the number one reason listed in Gears magazine was ......... dirty battery terminals

I didn't believe it myself, but after I cleaned them all up my tranny once again shifts like a dream. Give it a shot ... it's free !!

Good luck !!

 

sounds weird but thanks I'll try it.

 

I only run about 1700 RPM @ 60 MPH with 3.55 gears.

When I drive to work I do about 2 miles on the highway and if I leave my OD off I hit about 2500 RPM @ 60 MPH. It does sound like your trans isn't shifting into OD.

 

welcome to DF... maybe you dont have 3.55's in the rear. use this calculator http://www.differentials.com/calc.html to help figure out if you have the gears you think you do... if it's in OD then you most likely dont have 3.55 gearing.

best way to find out is to turn od off, get on the freeway and then turn it on... you'll see it upshift.

 

thanks for the input, I'll try these remedies

 

Hey. My truck is doing the same thing actually. It only does it once in awhile though so I know that it is not going into overdrive because the rpms stay alot higher than they should be. I replaced the speed sensor and the VSS and its still acting up. Any other ideas. PS- I thought the battery terminals were interesting but mine were clean anyways.

 

My truck (98 2500 5.9)has 4.10 gears and it runs well over 2000 RPM at 100kph = 62mph. I think it runs around 2400 but my tires are to short, they are P245's and I think they are around 28-29" tall....I need new tires lol! To repeat what steve05ram360 said. Are you sure you have 3.55 gears?