So my 92 donor truck had 3.53 gears and my 78 has 4.10 gears. I'm looking for a charts or something to help me figure out what tire size I need to keep the speedometer reading correctly. I have been looking online, but everything I've found has been for off-road applications.
Thanks, bud! Between that site and a tire size converter, i found that 8 will need 255/55/r18 or 255/60/r17. Not super stoked about the increase in ride height, but what can you do.
Apparently the gm/Chrysler thread is the same as toyota. Maybe you can go to a junk yard and yank a cable for cheep to test. https://www.ihpartsamerica.com/stor...qirrlIbj2Gx27PPxU3Wnt1RpzXgTtHiBoCpeEQAvD_BwE
Maybe this will help. I once did some tinkering with an online RPM calculator to help figure out gearing for highway cruising speeds with different tire sizes and my w50 transmission. I realize some people use a 23" tire on these trucks when lowered, but you can guesstimate. I couldn't really find anything local, so I was looking at buying a used higher geared 8" 30-spline differential on eBay, but they're all still like $250+ W50 trans gear ratios: 1st 3.28, 2nd 2.04, 3rd 1.394, 4th 1:000, 5th 0.853, Reverse 3.769 4.10 gearing @3510 RPMs: 26" tires - 78mph 25" tires - 75mph 24" tires - 72mph 3.73 gearing @3510 RPMs: 26" tires - 85mph 25" tires - 82mph 24" tires - 79mph 3.58 gearing @3510 RPMs: 26" tires - 89mph 25" tires - 85mph 24" tires - 82mph 3.14 gearing @3510 RPMs: 26" tires - 101mph 25" tires - 97mph 24" tires - 94mph
if you're not worried about the odometer been accurate, you can adjust the needle by holding the speedometer drum and removing the needle and refitting it in the correct position. I've done it on a couple of vehicles and it works just fine. let me know if you need for info.