School Me! Rear Differentials!

Big Tex

Big Tex

slowly but surely
Jun 25, 2012
7,951
207
0
Dallas, TX
I think the gay80 is about to go out in my 1500 and I don't know shit about gears. Any help/advice is appreciated. I will be running around 275/60r/20 (33X10.8X20) tires soon and they will be more mpg friendly than my mud graps. What gears (if any) will help my mpg's and be good for around town/highway driving. I do about 75% town, 25% highway. still want something that will allow me to get up and scoot. seems like my truck just bogs down when you want get on it. I'm getting 12/14.5 mpg now with the g80 and 33's.

Oh, and I'd like to have some gears that will cooperate with offroading (mainly mild trails and small puddles) and the occasional burnout :naughty: But srs, any and all help is greatly appreciated! :shake:



also, sorry for the fluster-cuck post. :crazy:

edit**
just found my paper with all my rpo codes on it, I have 3.73's on the g80 now
 
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according to this chart, my RPM's at 65 mph is 2469. I'm thinking I should be looking at some 3.91's or 4.11's.

diffratiochart.jpg
 
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stay with the 3.73's i have 33's and them and its not bad at all.

you have to realize, you change the rear gears you have to change the front too.

i would just swap over to a truetrac before the g80 blows up and takes out the gears. because as of right now, you can put your rear gears back in.
 
after reading those 2 posts, maybe I will just stay with 3.73, DNW to change front gears... may run a smaller tire as well. idk...
 
i knew from the time i bought my truck i wanted the rear rebuilt to get rid of the g80 and was planning on going to 4.11s next year since i'm in the same boat as you and have to do both front and rear. but the time bomb went off and screwed everything up so now i'm stuck with 3.42s which are brand new along with the truetrac so i have no reason to change them :banghead:
 
i like my 373's i had some weird noises coming from rear lasted about 2000 km's after i changed the fluids then it went away has been fine ever since ...

( i actually bought the truck off the guy and he said it needed a new rear-end so that showed in the price....12,000km's 8000 miles and countless of burnouts mudding and drifting and its still in there and doing fine.. i guess i have a good G80 ? ):csb:
 
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