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nonstop · 04-16-2018, 11:09 AM

Factory rear I believe is 28 spline. Only way to know for sure will be to pull an axle and count, as who knows what’s been changed in 30+ years.

As for gearing, you may want to actually consider stepping to a lower gear. Depending on cam and engine specs, you could be below the engines power band. You could actually see an increase in mileage with lower gears.

04-16-2018, 11:09 AM	#2
nonstop Registered User Join Date: Dec 2014 Location: Northern California Posts: 422	Re: Posi Rear End Factory rear I believe is 28 spline. Only way to know for sure will be to pull an axle and count, as who knows what’s been changed in 30+ years. As for gearing, you may want to actually consider stepping to a lower gear. Depending on cam and engine specs, you could be below the engines power band. You could actually see an increase in mileage with lower gears.