I just had my speedo re-calibrated for my new tires yesterday and this morning my ABS and Parking Brake lights on the dash came on, along with the door chime. I pulled over, shut down and restarted but they were still on. I'm going to go back to the shop that did it but wanted to get your ideas first.

 

Also, anyone know why HPTuners would show 3:73 as a gear ratio when the truck has 3.42's? Just curious about that one.

 

You probably have an OS from someone elses truck. Who did the tuning?

 

do you have HPT??sounds like he just has the wrong gear slection in there.

 

A local tuner did it with HPT. When he registered the truck it showed a 3:73 in the gear size so he copied it over. We ended up with a 33.2" tire size on the 3:73 to get the speedo right. According to my math 265-70R17 should be a 31.6" tall tire. I went out and started it up a bit ago and the lights are off now, maybe it was just a fluke. I'm going back this weekend and re-adjusting it for the 3.42's and 31.6" so I know it's right. I'll post up if the lights/chime happen again.

 

so you have 3.42's and 31" tires and your tuner put in 3.73's and 33" tires?the stock tune had 3.73's in it but you really have 3.42's??? something doesnt add up here.are you sure you have 3.42's?

 

Checked the RPO codes this morning. GU6=3.42 correct?

 

GU6 appears to be 3.42 gear. As others have said, I am guessing that the tuner used a previous tune and uploaded it to your truck, w/o confirming that it was correct. If he downloaded the OEM tune before messing with it, you should have him replace it, and start from there. No telling what else doesn't match on the truck.

 

I don't think he downloaded any tune. I only wanted the re-calibration. I will make sure he didn't download another tune though. Thanks.

Some more puzzle pieces for you;
The lights and chime came on again on the way to lunch. Happened at 60mph.
Happened again on the way back to work. At 55mph.
I drove around town a while and stayed at 35-40mph and the lights didn't come on.

 

Went back to the tuner today and fixed the gearing and tire size (3.42 with a 31.6" tire).

The lights still came on a 55mph though. There's no rubbing or anything in the fender well and no wires look broken so unless the tire installer fugged something up I didn't see I'm at a loss.

Next trip will be the dealership.