| 723 revs per mile = 27.89 tire diameter
| 755 revs per mile = 26.7135 tire diameter
|
| 5280 / 723 = 7.3029 multiply by 12(inches per foot) = 87.63485 divide
by PI(3.1415) = 27.89586
| 5280 /755 =9.9933 x12 = 83.9205 /3.1415 =26.7135
|
| My FSM for 2000 dak, page 22-6 shows
| 215/75r15 = 760 revs per mile
| 235/75r15 = 729
| 255/65r15 = 755
| 255/55r17 = 750
| 31x10.50x15 = 689
Jeff-
While I don't dispute your math. I double checked with less rounding! It
doesn't mesh with my data points. A 255-65-15 tire for example is dead on
28" according to Goodyear (28.05" if you do the math
[(255x2x.65/25.4)+15]). The BFG Radial T/A 295-50-15 is 26.7" tall and
requires 779 revs/mile @ 45mph. This is from the BFG spec page.
I can't explain the discrepancy. I currently have the 255-65-15 tires and
this is selected under [ABS] >>> [9 1/4 axle] >>> [Tire Selection] when I
viewed the scan tool at the dealer last week. I could switch to the 215,
but I'd imagine they would charge me something and I doubt if I'd make it
up. 755 to 760 is 2/3rds of one percent!
-STE
This archive was generated by hypermail 2b29 : Fri Jun 20 2003 - 11:55:52 EDT