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Heater63 · 01-21-2010, 02:51 AM

I am not an expert, but just went through this, and as msgross mentioned, 3:73 is the largest you can go on a "3 series" carrier. To go 4:11, et al, you have to change to a 4 series posi.

I just had a Detroit TruTrac posi put in mine, and stayed with 3:73, but I will be running 5 speed overdrive TKO 500 with 28 inch tire. 70 mph = 2200 rpm

Have you thought of going with overdrive? best of both worlds, you can have tall gearing and decent cruise rpm.

01-21-2010, 02:51 AM	#12
Heater63 Registered User Join Date: Dec 2007 Location: N Texas Posts: 580	Re: 3.73 gear swap for ???? I am not an expert, but just went through this, and as msgross mentioned, 3:73 is the largest you can go on a "3 series" carrier. To go 4:11, et al, you have to change to a 4 series posi. I just had a Detroit TruTrac posi put in mine, and stayed with 3:73, but I will be running 5 speed overdrive TKO 500 with 28 inch tire. 70 mph = 2200 rpm Have you thought of going with overdrive? best of both worlds, you can have tall gearing and decent cruise rpm. __________________ 292 + TKO500