BFG 315/70/17 tire and level kit questions/opinions ?

[miller_wb]

FWIW: I have an '03 HO/3. 73/Auto. I put the 315/70/17's and the Daystar non-metal spring spacers on my truck at 5K miles. I have 56K miles now. Empty and trailering a car to the track occasionally, I did not experience a significant difference in mileage. I did take it to the dealer to get the revolutions per mile set to compensate for the larger tires. The only thing I would do differently is to get the front end aligned after adding the spring spacers and tires. At 51K on these tires, the outside edges on all four tires are slicks. I rotate every 5K and I am running the maximum tire pressure.

 

[MickeyMiller]

I went with the 315/70/17 BFG ATs without the leveling kit. Had aleignment checked, but not changed, when I put the tires on. I rotate every 6K... got over 35K on the tires now and still have 60%+ tread. Slight rubbing on the lower arms at full lock, but nothing to worry about. Milage not affected... got 19. 2 (calculated) on my last trip (empty, 75 - 80 mph). Like the lower crusing rpm. Eliminated the axel tromp I had with the stock Michlins. '03 QC SB 6-speed 3. 73, Edge box... "the only reason you need lower gears is if you don't have enough engine"... the Cummins is enough engine.

 

[NLamke]

5 MPG less????? Wow, I just got back from a couple hundred miles on the interstate, cruise set on 75 mph and got 18. 9 mpg. The best I ever got with stock tires is 19. 5 mpg. Not much difference there. I've got the 373 gears, and run 1900 rpm at 75. I've only got 4,000 miles on my truck and am hoping to get a little more mileage as time goes on. And to the question about a leveling kit... You don't need it to run the 35's, but I think it looks a lot better with it.

 

[JVolpe]

I have had the DayStar 2" leveing spacers and 315s on stock rims for over 18000 miles now with 48re and 3. 73 gear. I did have a full front end alignment when the leveling kit was installed, the tires and shocks came right after that. I saw between 1-1. 5mpg drop in city driving. Did not see any measurable difference on the highway. I am running close to the max tire pressure and see a slight cupping wear, this is do to the 8" rim width. I rotate every 8000 miles and expect to get 55k-60k out of these tires.

 

[ECappleman]

I have had the DayStar 2" leveing spacers and 315s on stock rims for over 18000 miles now with 48re and 3. 73 gear. I did have a full front end alignment when the leveling kit was installed, the tires and shocks came right after that. I saw between 1-1. 5mpg drop in city driving. Did not see any measurable difference on the highway. I am running close to the max tire pressure and see a slight cupping wear, this is do to the 8" rim width. I rotate every 8000 miles and expect to get 55k-60k out of these tires.

I know you do, you took me for a ride in it.

But you didn't let me drive it, so it was hard to tell. :{ But then again, I probably wouldn't let me drive it either. :-laf

 

[ECappleman]

But nobody has puled with the 315s and 3:73 gears?

 

[JVolpe]

ECappleman,



Call me, we need to meet some time not in 5:00pm Houston traffic. Your welcome to drive the truck. We can even hook up your load if you want.

 

[Garry Verheyden]

I have an 03 3500 DRW 4X4 6spd(3. 73) My dad has an 03 3500 DRW 4X4 6spd (4. 10) We both are quad cab. We both have an identical 10' slide out camper. We were trying to get the best mileage we could on a 400 mile round trip. We travelled together doing about 55MPH avg. speed. He got 15 MPG with his 4. 10s I got 15. 8 with my 3. 73s. Identical trucks/speed/weight etc.

I got 5% better fuel economy and I had 5% lower rpm's. Coincidence???

I would stay with the 3. 73 from my first hand experience.



Garry