Center bore for 6 lug?

[Tx Firefighter]

Originally Posted by incoma

I image you're referring to your green stepside that you sold? I didn't realize you had 17"..

The green truck had 15 inch Cragars on it.

My old 72 has 17x8 Torque thrusts with 5" B.S. on all 4 corners.



Tires are 275/60/17 in rear and 255/50/17 in front. ECE 4/6 lowered with no rubs or interference anywhere.

[GreyHoundSteve]

TX firefighter, I plugged your #'s into the tire size calculator and it looks like the truck above has 29.99 Diameter and 10.82" width on the rear and 27.03 Diameter and 10.03 width on the front. If you had 5"bs all around and im planning on running 245/40/20 up front that have a D=27.71 and W=9.64 with the rims having 5 1/8"bs and the rears will be a D=29.30 with W=10.43 with a rim backspacing of 5.62 when that means we have a difference of only +.68"D and -.39" W and +1/8" bs on the front
-.69"D and -.39" W and .6282" bs on the rear
Assuming that you had and extra 3/4" diamter room up fron i should be fine there and if you had an additional 1/4" of bs in the rear i should be fine .... right?

My math looks something like this:
Your tire combo 27.03D 10.03W 5"bs Front
My Tire Combo 27.71D 9.64W 5 1/8"bs on front
A difference of +.68D -.39W +1/8bs

Your tire combo 29.99D 10.82W 5"bs Rear
My Tire combo 29.30D 10.43W 5.6282"bs Rear
That gives us -.69D -.39W +.6282"bs

Or what about this combo:

***********************
255/50/17= 27.03D 10.03W
255/45/20= 29.03D 10.03W
Difference= +2D Same

275/60/17= 29.99D 10.82W
265/40/22= 30.34D 10.43W
Difference= +.35D -.39W

The one i just posted above would be optimal because the tires have a bit more sidewall on them. Would either of these combos work? My truck is a 67, did the have different width rears from a 72?