Would you re-adjust ?

Yes it came with 245's and with the 285's the speed wasn't off as much as you'd expect, about 4mph at 70. The 285's were not worn but man it looks a LOT lower now. I expect I'll be a little nose low now if anything.

On a side note, anybody running 285/75/16's on stock 2500HD rims should think twice before towing heavy....it's not fun !!

I doubt that it will make a difference, but check it anyway, very easy to do!

Didn`t that year GM come with 245`s?

CampingN.C. wrote:
I've gone from 285's to 265's. The truck sits noticeably lower now, at least an inch. It's a DC and I'm not sure it's worth fooling with for such a small adjustment.
Thoughts ?

It's not as much as it looks.

A 285 is only ~1.1" taller than a 265, which would change the hitch height 1/2".

If the 285's were worn out then the change is even smaller, maybe 3/8".

I doubt you need to readjust the DC based on the tires, but as was mentioned I would get the speedo fixed.

Have you thought about flashing the computer to get the speedo, odometer, and MPG right?

As above and if the trailer is too nose low you may need to adjust the ball also

I would readjust too. Doesn't take long, and to be honest the reward can be pretty great. I've pulled over on the Interstate to readjust when my load was that much different. I had the old style, all I used to do was crank it up tight, loosen the U-bolt nuts off, hit the plate with a small sledge hammer to pop it into place and tighten again. Took no more than five minutes, once I found the wrench and the hammer... :)

Brian

Yes, I would. Make sure the rig is straight and the cams are centered.