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mr48chev · 02-27-2023, 03:55 AM

A 7.50 20 tire is 35.6 inches in diameter or real close to it. In theory with that rear axle 44 inch tires would drop the rpm 552 at 50 mph from 2893 to 2341 with a 1 to 1 output ratio on the trans.

Still you would have to have very expensive custom wheels made to fit that axle and if you swap to something different on the front you are going to have two different lug patterns anyhow Plus the 2 speed adds 150 lbs to an already serously heavy rear axle. The axle ratios are 8.10 low and 6.13 high and unless you are planning on hauling full loads of gravel out of a pit the 8.10 isn't going to do you much good out side of giving you another set of gears to shift though.

02-27-2023, 03:55 AM	#11
mr48chev Registered User Join Date: Jul 2007 Location: Toppenish, WA Posts: 15,342	Re: 51 5 window dump truck A 7.50 20 tire is 35.6 inches in diameter or real close to it. In theory with that rear axle 44 inch tires would drop the rpm 552 at 50 mph from 2893 to 2341 with a 1 to 1 output ratio on the trans. Still you would have to have very expensive custom wheels made to fit that axle and if you swap to something different on the front you are going to have two different lug patterns anyhow Plus the 2 speed adds 150 lbs to an already serously heavy rear axle. The axle ratios are 8.10 low and 6.13 high and unless you are planning on hauling full loads of gravel out of a pit the 8.10 isn't going to do you much good out side of giving you another set of gears to shift though. Attached Images __________________ Founding member of the too many projects, too little time and money club. My ongoing truck projects: 48 Chev 3100 that will run a 292 Six. 71 GMC 2500 that is getting a Cad 500 transplant. 77 C 30 dualie, 454, 4 speed with a 10 foot flatbed and hoist. It does the heavy work and hauls the projects around.