99 rearend in my 07C?

[bluex]

I've been looking for a different rearend for my truck to get a better gear ratio. I currently have 3.23's and I found a rear from a 99 with 3.42's. My plan was to remove the disc brake stuff from the donor rear and put my drums on it.

I'm holding out for a 3.73 posi rear, but they are $$$$ and this one is a pretty good deal. No idea on the milage though, it was a fleet truck as it has some companies name on the door.

Anyone done this or know of something else that changed in the axle assemblys when they started putting drums back on in 04 or 05? I can get this complete axle from disc to disc for less than a set of gears and an install kit....


Thanks,
Paul

[bighaas79]

would be so little of a jump in ratio it wouldn't be worth it i don't think

[bluex]

Ya I found a gear calculator and its only going to gain me about 100 rpm which will put me back to stock rpms with the larger tires. I went from 245/70/17 to 265/70/17.

Guess I'll hold out for a 3.73, but it will only gain me 250 or so rpms. I did call two local 4x4 places about having a new set installed in my rear. Was quoted $720 from the first one and $790 from the second one.

The biggest problem with it is, the 3.06 1st in the tranny that drops to 1.69 in 2nd. When you slow down to turn or for traffic it takes it forever to get back up to speed, unless you make it downshift to first, then you zoom off. 2nd in the tranny really needs to be a 2.xx, but I'm not going there. I think I can get a OE 3.73 posi rear at the local yard for around $600. I'll just keep saving for that I guess...

[bighaas79]

I'm guessing this is a 2wd truck? If not the front dif gearing will need to be changed if the rear is.