2006 Silverado 1500 Z71 a few questions

azchevy · November 16, 2006

I have a few Q's regarding my 06 silverado z71 1500 that I really couldn't find conclusive answers to using the search function

1. What is the largest tire you can fit without rubbing? I currently have 265 70R17 stockers on there and I want some suggestions on what I should run when I upgrade ( not tire model but tire size)

2. Did you but a leveling kit on? if so how is the ride? the gas mileage?

3. Is a PCM worth the money? Does it really help power and gas mileage?

4. How often do you change the auto tran fluid? The book says 100K, I am thinking a filter and fluid change every 30K

5. Same goes for the diffs and the transfer case. I am thinking every 30K the book says 100K

Thanks for the feedback

ZZebes · November 17, 2006

285-70/17 with some MINOR trimming

Had a leveling kit but the aftermarket key broke and that really sucked so no more leveling kit

God yes is the PCM tune worth the money

follow the book (Change the filter every 30k-50k if you feel in necessary but not the fluid)

follow the book (diffs at the first oil change to get all of the break in gunk out)

chanswork · November 17, 2006

1. Without any mods, 265/70/17 is the biggest tire you can squeeze in there.....on a 17 inch rim.

2. Leveling kit installed up front raised 2 inches, rides better, looks better. gas mileage doesn't change.

3. I always wondered what's a PCM tune......

4. Hear there are more problems with the tranny than the engine, so going by the book at 100k might be too long. I do mine every 50k and it's been good so far....now 85k

5. Would think 50k would be a good time to change the fluids here too.

Maintainance cost is relatively low when you compare it to a tank of gas. $50 for 300 miles on gas........as oppose to $100 on a tranny fluid change every 50k....makes sense to do it more often.