L285/75/r16 tires with 4.10 rear

[Keith Richards]

I recently put new tires on my older chevy,and for for kicks the other day,switched them over to my 6.5 truck to see if they would fit(same size rims and lug pattern)and I am real pleased.I think theyre staying on this one.It seems to have brought the gearing much closer to where I've been wanting them.Seems like 3.73 ratio now, I'm not sure.It definately brought the rpms down on the highway,and seems to have thrown the speedometer off about 5mph,again not sure until,or if I get the speedo recalibrated.Anyone done this?I'm not sure whats going to happen with the milage,but definately like the bigger meats and lower rpms.The truck sits up much higher than I thought possible without a lift and theres no rubbing.It does look a little close though,looks like the wheel opening is almost too full,I would like about 1" or 2" lift without going the body lift route.Maybe just up the torsion bars,and add a small block/spacer under the rear springs.Anyone gone that route?It's not totally necesarry though,the tires fit.

[arrowheadracing]

I have 285 75's on my 4x4 with only tight turns ( almost full lock ) in reverse and sometimes going forward if on uneven ground will it hit the front plastic. I too would like to lift about 2 ". I found a place I can order the front cams and rear blocks for around $80 for everything. My truck supposedly came with 3.73 gears, but I believe it has 4.10s. My rpm at 65 mph is about 2250. I havent reflashed the vssb yet, and that was taken before the tire change ( stock 245 tires ). I love the way the truck looks. But I did notice a drop in mpg to spin those heavy big tires. Almost not worth the loss , but damn it looks good.

Todd

[matt-max]

we did the torsion bar crank, moved the front bumper out a bit and added 1" spacers in the rear to the 96 2500hd. it looks very cool and drives great too. it has the 3.73's and is lacking a bit down low even with the extra power.

totally transforms the truck from the stock wheel/tire combo....but requires quite a jump or step for short-legged folk now to get in!

matt

[LilRed Turbo]

Todd
If you haven't recalibrated the VSSB the larger tires will make the speedo read slower than actual speed. That also means the odometer will be recording fewer miles than actual. That will make your fuel mileage appear low. ;)

[norm]

Also worthy to note is that without changing the vssb, your indicated RPM @ MPH will not change with tire size change (the tires are not between the speed sensor and the engine). You have to estimate the RPM drop by the speed difference before changing the vssb.

Todd, it seems to me 2250rpm @ 65mph is right for 3.73. I have 4.10 and IIRC my rpms are higher at 65.

With 285/75 tires, watch the front bumper corner for potential contact with suspension compression and wheels turned about half way??