7.5" rear end gears

[LukeZ]

I got a nice chunk of cash for my birthday and I was thinking of putting it towards my car. I'd like to to get a lower set of gears for the rear end.

Right now I have a 7.5" open rear with 2.56 gears. It's all stock. I also have a 200R4 with overdrive.

Two things; first, is changing the ring and pinion gears out something you can do by yourself with some jackstands and wrenches? And second, Im thinking about going up to 3.42s (I would do 3.23s but couldn't find any). On Summit, I'd want to get a "thick" set right? Because I have a 2 series carrier and regular 3.42s are meant for a 3 series?

Thanks!

 

[olds307 and 403]

Yes, thick gears and 3.42 gears are about perfect unless you drive 80 mph a lot. At 60 mph with stock height tires, 1850 RPM.

 

[Pedrolif]

Hang on, I'm interested in this since my rear end is 2.29. What is this thick gear?
more info, 15" rims instead of stock 14's, 350 trans, so no 4spd overdrive, but better then the 250c that it had when i got it.

 

[Turbolq4]

I got a nice chunk of cash for my birthday and I was thinking of putting it towards my car. I'd like to to get a lower set of gears for the rear end.

Right now I have a 7.5" open rear with 2.56 gears. It's all stock. I also have a 200R4 with overdrive.

Two things; first, is changing the ring and pinion gears out something you can do by yourself with some jackstands and wrenches? And second, Im thinking about going up to 3.42s (I would do 3.23s but couldn't find any). On Summit, I'd want to get a "thick" set right? Because I have a 2 series carrier and regular 3.42s are meant for a 3 series?

Thanks!

Setting up rear ends is an art form. It takes a bit of experience, not something I would recommend you just jump into and throw together. Thats some junk I would do....

 

[DROLDS84]

Yes, thick gears and 3.42 gears are about perfect unless you drive 80 mph a lot. At 60 mph with stock height tires, 1850 RPM.

I'm assuming your rpm estimation is with the 2004r, running a turbo 350 in my sons car and changing rearend gears this summer.Wanting to drive the car out of town and not sure what gears to go with.

 

[drogg1]

You'll want the thick gearsor a spacer and the thin 3 series gears.

As Turbolq4 said though it is not something to just slap together. You can do it on jack stands but to do it right you'll need a few tools (dial indicator, gear marking compound,etc) and the patience to take the gears in and out to make sure the clearances are where they need to be.

Should be 20+ threads on the site discussing this.

Also, happy birthday!

 

[LukeZ]

Maybe I'll pay a shop to do it then because the car is my daily and I can't afford to mess it up

I think I'll go with the Summit brand
https://www.summitracing.com/parts/sum-741014/overview/

I think I'll get this installation kit too since it comes with the marking compound, bearings, a gasket, etc.
https://www.summitracing.com/parts/sum-g7921k

Other than that, there's nothing else needed right? The shop should have the dial indicator and stuff?

 

[olds307 and 403]

I'm assuming your rpm estimation is with the 2004r, running a turbo 350 in my sons car and changing rearend gears this summer.Wanting to drive the car out of town and not sure what gears to go with.

Yes 2004R AND a lock up torque converter which drops it another 300 RPM. I would go 3.08 max if you are running a stock height tire. That puts you around 2800 RPM without a lock up converter.

 

[olds307 and 403]

Maybe I'll pay a shop to do it then because the car is my daily and I can't afford to mess it up

I think I'll go with the Summit brand
https://www.summitracing.com/parts/sum-741014/overview/

I think I'll get this installation kit too since it comes with the marking compound, bearings, a gasket, etc.
https://www.summitracing.com/parts/sum-g7921k

Other than that, there's nothing else needed right? The shop should have the dial indicator and stuff?

Any shop that does differentials will have the necessary equipment. Talk to the shop, they may have a preferred brand of gears. It isn't that hard to do. Pinion depth is critical and I eye balled back lash, although a dial indicator is best. Junkyard gears and carrier from a S-10 or Astro Van are an option to do it cheap and on your own, just buy a shim kit and solid pinion spacer. Crushing the crush sleeve can be a b*st*rd. If you like flooring the pedal, improving the gear will make it much easier, upgrade the spider gears, mine exploded an took out the pinion. I upgraded to the Yukon spider gears, the stock ones are super soft.
https://www.summitracing.com/int/parts/yga-16048/overview/

 

[DROLDS84]

Yes 2004R AND a lock up torque converter which drops it another 300 RPM. I would go 3.08 max if you are running a stock height tire. That puts you around 2800 RPM without a lock up converter.

Running 28's on the back.I think 3.23's will work well.Thanks