I recently hauled a trailer over the mountains here in Colorado in my 98 ram 1500. Before the trip everything was functioning properly in my truck. About 2/3 of the way thru my trip I was pulled over for doing 73 in a 65 as well as another issue that confused me. I had my cruise set at 66 when I was clocked and have since seen that my speedometer is a good 5-7 mph over all the time. I have no clue what caused it or how to fix it. Furthermore when I was pulled over he said he had watched me ride my brakes for the last mile and a half. I wasn't on my breaks, my e-brake was not engaged either. So while I was on the side of the road I shut my truck off and sure enough my brake lights stayed on. I pulled negative battery cable and when I reconnected terminal lights were off. Anyone have any ideas what could cause these random issues with my truck?

 

what size are your tires?

The brake pedal switch could have been stuck and/or a ground issue with your wiring. Try to inspect the wiring harness starting from the back. Perhaps pull the rear housing out to look at the ends. Unseat, reseat, etc. Get some dielectric spray to shoot on the connections while you're at it.

I'm sure others have some suggestions.

What road were you on? I-70? lol

 

Right now it has 285/50R20 tires on it. PO wanted a street truck I guess... Plan on changing that out when funds are avaliable. Farm life and these tired do not get along. Got her stuck in wet grass a couple weeks ago. I was lind of assuming the brake light issue may have had something to do with my wiring for trailer lights. Climbed under to change license plate lamps and wiring is a wreck so I suppose that's a good place to start. Lol I was on Hwy 50. I don't trust these tires on any interstate especially the way Colorado weather has been lately

 

I am running 285s on mine. And at 70 mph, I am off about 10% (actually running 77mph). Couple tickets to verify it from different troopers......

So there's your speedo problem!

 

would that account for it being off all the time. Its off whether im doing 30 or 70.. And I never had that issue til I hauled that trailer thru the mountains. Before that I never had issues with it being off

 

Yes. All the time. The tire circumference is larger, therefore for each revolution, you are moving farther than the the system calculates. The amount of difference is about 10%, so you will be running 55 when reading 50, 77 when reading 70, etc.

 

Those tires work out to approximately a 31 inch tire.... which really isn't all that much different than stock.... unless your truck came with 225's, or some such. Any idea what the stock size was?

 

to be honest I have no idea what stock size was. I purchased the truck used back in February. It already had the 20inch tires on there... Owner said he bought it to make it a street truck but changed his mind because he didn't realize how easy the plenum plate replacement was. It drastically needed replaced when I purchased

 

Stock for my 2001 1500 4x4 SLT is 245 75R16