dana 70/ dana 60?????

[87crew]

just got a 87 c30 crew with 6.2/th400/205. i want to lift it and go with hummer wheels/tires. what is my stock gear ratio in the 70/60 combo? will this ratio be ok with 37's and still tow 5000lbs decent?

thanks

 

[obijuan]

its luck of the draw on what was ordered, check the RPO code sticker, usually located in the glove box, or driver side inner fender.

also there are tags on the axles themselves that can tell you. but i have never towed with a 6.2 so not sure on how good it does.

 

[87crew]

its luck of the draw on what was ordered, check the RPO code sticker, usually located in the glove box, or driver side inner fender.

also there are tags on the axles themselves that can tell you. but i have never towed with a 6.2 so not sure on how good it does.

checking the code how do i tell RPO ratio? any idea what is common in the c30 with these axles?

 

[Hogback Fabrication]

First, a C30 is 2WD and a K30 is 4WD.

With the diesel it will probably have higher (numerically lower) gears. I'd say 3.73 is most likely. That truck will not be too happy towing 5K but if you have a good trans cooler and change your trans fluid and filter often it will survive but it will be SLOWWWW.

Gears will help some but with a diesel you can't really rev it either, the big thing that's holding back how much of a dog it will be is the 6.2L.

 

[1BEATK5]

look on the sticker in the glovebox for gt4. thats 3.73. if thats not listed, then they are lower. i don't remember off hand what 4.10 or 4.56 is.

 

[87crew]

thanks for the info. with a lift and 37's what gear ratio would work best? 4.56? as long as i can get it back to close to stock ill be happy.

 

[Hogback Fabrication]

thanks for the info. with a lift and 37's what gear ratio would work best? 4.56? as long as i can get it back to close to stock ill be happy.

We still don't know your stock ratio, so can't really comment on that.

Again, the diesel is going to suck on the highway if you run deep gears but in the same right it needs every bit of help it can get.

 

[87crew]

We still don't know your stock ratio, so can't really comment on that.

Again, the diesel is going to suck on the highway if you run deep gears but in the same right it needs every bit of help it can get.

just figured out my gear ratio its got 4.10's

 

[Hogback Fabrication]

just figured out my gear ratio its got 4.10's

I think I'd try that setup with your current gears, did you feel it was geared too low as it was?

To get near stock gearing you'd be between 4.88's and 5.13's.

 

[blazinzuk]

I have 4.56s in my 60/70 wanna trade gears?