Differential gear swap. Ratio?

Chevytothebone · February 15, 2014

I own a 2007 Classic Silverado. It has a V6 with a manual trans. I was recently involved in a wreck which left me with a non repairable differential. I wasn't able to find a used axle with the same gear ratio as mine but was told that the axle off of a regular V8 would work as well. The only difference would be higher rpm's and lower gas mileage. I went ahead with the install but now i'm wondering if its possible to just swap out the gears in the differential.

so... is it possible? I mean assuming that the gears from the old one are in good condition.

Genuinefine409 · February 16, 2014

It is possible and it is done all the time. if you have never done it before, I would suggest either taking it to a reputable shop or reading up on it a ton before attempting it. The last thing you want is a noisy rear. What ratio did you have and what ratio do you have now?

Chevytothebone · February 16, 2014

I believe my original gears where "GU5 Rear axle, 3.23 ratio". I honestly don't know much about the one that's currently on my truck. All I know is that it came off of a 1500 V8 Silverado. I'll be taking on the job my self... I'm a "If you want something done right, you have to do it yourself" kind of guy. I have a very steady hand with a $#!t ton of patience. I'll take your advice on reading up on it. Thank you for your help!

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kstruckcountry · February 16, 2014

It's a pretty complicated procedure. I like lower gears. I can get 18 with my 3.73's and that's the best mileage I've heard of with a 2006 5.3 4x4 like my setup.

You should correct your mileage for the new axle ratio and see if your mileage has actually gone down.

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Chevytothebone · February 16, 2014

Glad you mentioned that. Though I don't know how. Any ideas on how I would go about doing that?

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kstruckcountry · February 16, 2014

You need to know the rear gears to do it. Once you know the gears it's easy.

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Big Whiskey · February 20, 2014

I would definitely run the lower gears that are in the new axle. It will accelerate better, tow better, and might get just as good MPG as before. Once you find out what the new gears are, you can get a tune to fix your speedometer...then you can also calculate your new MPG accurately.