changing the rear end gear in my 77 dually

thats like 40miles south of here and he buys from US gear

well arent you special.......

maybe special ED

i found us gear and it says from 77-91 they made a dana 60, and the dana 80 from 88-up, and rubbed the dirt off the webbing of my rear and it has 09 77 stamped on it, does that mean it was made i 09-1977 ? do you measure the ring gear from the outside diameter or the inside? i hope mine is not the dana 80 , i bet that gear set is expensive as hell!......i hate it for ya dragnasty......

It is most likely not a dana 80, but a dana 70. I have an 89 4x4 crew cab with a dana 70 in it and a dana 60 in the front. The 60, 70, and 80 all have 10 bolt covers, but they are all different. The 60 has a 9.75 inch ring gear, the 70 has a 10.5 inch ring gear and the 80 has the (11.25 or 11.5) inch ring gear.

Also, if you are looking at the axle from the back, 4 to 6 inches from the chunk on the right axle tube is the BOM number, which will tell any axle shop what it is. It is a series of 6 or 8 numbers, I think, and they are very small ... about 1/8 inch tall. If you do not have a tag on the differential cover, then the BOM is the only way to tell without pulling it apart.

I have a DANA 70 HD in my 86 dually, and I swaped out the 4.11 for a 3.56.
But I also have 26" tall tires, and there doesn't seem to be a lack of power or anything,but as far as I can tell, but I don't pull anything with it, yet.

thanks twisted,,, im going to try the 3.56 and see how it goes.......im not going to tow with it anymore so i hope it will be ok and not bog the motor down to much............