Gas milage---Tires?

[mrhab68]

I currently have 265/75-16 tires on my 2003 Silverado 1500HD crew cab 4x4 truck. It has 4.10 gears and I am getting about 13 mpg. I will pull a 30' camper 2 or 3 times a year and haul my tractor a little locally. Will 285/75-16 tires hurt or help my milage? I haven't pulled anything with it yet but it seems to have plenty of power what little I have drove it. I bought this truck the Friday before Christmas. Monday after Christmas a deer hit me starting at thr right front fender and went all the way down the side, fender, hood, both doors and bed. Sure made me sick. All fixed now just burning a lot of gas. Will the 285's clear on the front without cranking up the torsion bars? What are your thoughts on a Bully Dog E-3 programer. I bought one but have not installed it yet. I want to get this P1516 code problem cleared up first.

[j cAT]

Originally Posted by mrhab68

2003 Silverado 1500HD crew cab 4x4 truck.

It has 4.10 gears and I am getting I want to get this P1516 code problem cleared up first.

so your post is concerning this failure code P1516.....

this is quite common on you vintage vehicle ...there is a post currently on here that has had this same issue...

taking the time and reading through these forums you will find that this is a GM defect ..the throttle sensor OF the intake manifold gets damaged by chemicals and other contaminates...It is possible its just the wiring connector to it ...

after you check all this out 90% of the time the upper intake manifold will need replacing...the sensor iself , is not replacable ..


on tires , the bigger the tire , the more friction more fuel used..

those 285 are quite large for a small 1500 truck ...also those 4.11 gears are not too common on this 1500...15 MPG is about right ..so your a little low on the MPG >>>.

with my 3.73 4X4 I get 18-19 hwy..70 MPH>>.

[mrhab68]

I thimk I have solved my code P1516 problem. My truck is a crew cab 4x4 1500 HD. My understanding is these were only avaliable with the 6.0 engine and 4.10 gears. It seams geared too low is why I was asking about the larger tires. It is turning about 2 grand at 60 mph. My 94 GMC ext cab Z-71 had 3.73 gears with 265 tires and it ran about 2200 at 65 mph.

[j cAT]

Originally Posted by mrhab68

I thimk I have solved my code P1516 problem. My truck is a crew cab 4x4 1500 HD. My understanding is these were only avaliable with the 6.0 engine and 4.10 gears. It seams geared too low is why I was asking about the larger tires. It is turning about 2 grand at 60 mph. My 94 GMC ext cab Z-71 had 3.73 gears with 265 tires and it ran about 2200 at 65 mph.

my 2000 5.3L 4X4 3.73 diff turns around 2100 at 70 mph...

the truck you have is basicly the 2500 with the 1500 frame...1500 tranny..

with the engine and diff you have and the heavier springs you can tow a heavy load...

I still think you should be getting 15 MPG...

this 1516 code is an intermittent failure...you may go a week or two then it will strike ...

this failure however a PITA , is better than the toyota runaway engine throttle,,,they have no protection...

family member has the 05 avalon ..

my 2000 has the throttle cable ...but back it 2003 GM somehow got by NHTSA on this F up ! probably did what toyota did hire some NHTSA employees to hide the problem ...