I just purchased a 98 Ram and the ABS and Brake light are on. I just had the brakes serviced they work great. I have read online that if these lights are on and your speedometer doesn't work until 25mph that you need to replace the ABS speed sensor on the rear diff, but my speedometer works just fine. The lights aren't always on either. I drove the truck today about 3 miles to get gas and they came on rather quickly, but on the way home they didn't come on at all. The truck does have a problem sometimes shiftingat low speeds...is there another speed sensor somewhere else? The guyI bought it from told me it needed a speed sensor ($35 to $45), but I'm not sure which one I need and if this will fix my ABS and brake light issues.
Any experience or advice you guys have on this issue would be great! THANKS!!!

 

Don't know if this will help but I just resolved a similar problem. The ABS and brake light on my 95 ram stayed on all the time. Brakes worked fine. I replaced the electronic control module (computer that monitors the brake system located under the dash) and that fixed it.
It might help you track down the problem by having a mechanic retrieve the trouble codes for the brake system. Good luck.

 

Just an afterthought; I don't think your transmission problem and ABS problem are related. I'm no expert but I've had problems with both.

 

Thanks for the info...I will check it out.

 

The ABS and Brake light comes on and goes off all the time in my father's 98, usually if it is on when you turn it on, you just turn it off and turn the key back on and they are gone.

 

Speed sensor on the rearend. Just because the speedo works doesn't mean it's not bad enough to make the abs and brake light come on.......

 

Dude, I replaced the rear end speed sensor from a junkyard unit (about 10 bucks), and the lights went off right away.

FYI, my truck has only rear ABS, replacing the module could be more expensive, that is the reason why I replaced the speed sensor first, if that does not fix it, then I sugest replacing the module.

Good luck...

 

Thanks guys...I'll start with the rear-end sensor and go from there.