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**G&R's57GMC** · 03-07-2018, 12:43 PM

Yah the 2.75 is waaaay to high making 4th come in at 65 mph and then at 1500 rpm. Talk about gear hunting. 4-3 3-4-4-3 at light throttle

If you are using a 28" tire 4.11 would work great or maybe a 3.90 but nothing lower.

This would give great acceleration in all gears and decent power in 4th with a low rpm.

Remember that the gear spread in the 700R4 is about 1000 rpm between gears .
Use the tightest converter you can get and make sure it locks up at the lowest speed possible.
Ask me how I know.

03-07-2018, 12:43 PM	#4
G&R's57GMC Senior Member Join Date: Aug 2010 Location: Shasta Lake, CA. Posts: 1,619	Re: Rear end ratio for 700R4? Yah the 2.75 is waaaay to high making 4th come in at 65 mph and then at 1500 rpm. Talk about gear hunting. 4-3 3-4-4-3 at light throttle If you are using a 28" tire 4.11 would work great or maybe a 3.90 but nothing lower. This would give great acceleration in all gears and decent power in 4th with a low rpm. Remember that the gear spread in the 700R4 is about 1000 rpm between gears . Use the tightest converter you can get and make sure it locks up at the lowest speed possible. Ask me how I know. __________________ Glen & Jane's Rides ‘57 GMC NAPCO Long Bed V8 4 speed Bought 2008 7 other cars & trucks , 5 trailers '56 Chevy Long Bed I6, 4 speed Bought 1990 Sold 8.22.2020 ’56 GMC Suburban Pickup V8, 4 speed Hydramatic Bought 1996 Sold 10.11.2020 My Other Tinkerings http://67-72chevytrucks.com/vboard/s...75#post8967275 Last edited by G&R's57GMC; 03-07-2018 at 12:57 PM.