Rear gear question
 

Since the wifes new(to us)vehicle broke down (long story on that) i am now daily driving my truck again. I am very happy with this and would have all the time but couldnt justify letting a vehicle sit that cost me money monthly unlike the truck. Any ways, i will be driving my truck everyday for a few months til next spring. It is a '72 C20 with 4.11 rear gearing. i drive 7 miles to work and with our winters here i would like to change the gears from being a one-wheel-wonder open diff. for better traction when its not so nice out. This was built a work truck when new and still is so i do not want to compromise that. I pull a trailer from time to time also. what is your opinions? what are you running or had good luck with? ive done some research and liked the sound of a powertrax system. are these suitable for my needs?

Re: Rear gear question
 

You can drive it into a shop asnd have them install a brand new posi in a day for about $1000

Re: Rear gear question
 

The thing about a powertrax is they 'cog' when going around corners. This isn't bad if you're making a 90 degree turn from a stop in snow but get into a fairly sharp turn at 30 mph in snow and your powertrax can spin you when it cogs. An Eaton center is a clutched unit and will engage and disengage smoothly. Mo Bettah for driving in snow.

Re: Rear gear question
 

I have a "lunch box locker" in my 12 bolt. 3.08 gears. I did have a perp it was free! not a powertrax,but it's been in there 3 years now.I love it.They are pricey new but very easily installed.I like the click you get when turning.Kinda like a countdown to smokin' both tires!!
Just my opinion!

Re: Rear gear question
 

I added a Yukon post in my truck and Camaro, for me they work great....

Re: Rear gear question
 

eaton or dana

Re: Rear gear question
 

It is a Dana 60 with 4.10 gears. Anybody have part numbers or good places to buy from?

Re: Rear gear question
 

Also how much do they reduce mileage? I get the brick on wheels but I'm getting 12 mpg now. Don't want to drop it to 8 mpg

Re: Rear gear question
 

A heavy vehicle is not something one should have ANY expectations of getting any respectable MPG out of. It takes torque to get the thing to move and to keep it going....easily. Put a high gear in it, like a 3.00:1 and you'll be lugging the engine all the time. Not a good thing. I have had heavy cars and pickups. Any engine/gear selections will all be made on the power side of things, not MPG side. Easier to drive, and more fun to drive.

12 is actually pretty good MPG!!! I would NOT change the gear ratio!!! the MPG difference will disappoint you. I'm with you on the posi idea. Been in situations where 2 wheels spinning would have made a difference.

Re: Rear gear question
 

12 is good for these trucks and the weight of the vehicle. like i said i fully understand that im driving a gas loving truck and dont mind at all. im not going to change the gears from 4.10 because i love my towing/hauling ability with that gear. i just want to use a locker or something for better traction in the snow. i just dont want to bring it down to like 7/8 mpg. why pay that much more in gas everyday to have something else you would only need a few times

Re: Rear gear question
 

these trucks are not really that heavy. its the rear end gearing and the horsepower ratings that kill gas milage. and how you drive it. My 72 c10 3 spd/307/373 gears gets 13 maybe 14 mpg. It will do some work though!

Re: Rear gear question
 

I'm a believer in overdrive. 700R4 with 3.73
I just put in a eaton E-locker spool in this week.
We'll see how much change it makes. I suspect not a lot
on the freeway where it's mostly straight line driving.

Re: Rear gear question
 

these are some of the best work trucks ever imo. i have done way more with my truck then i could ever do alot of newer model 3/4 tons. Ive been reading up on lockers and alot of people are saying they are worse for snow and ice. so im needing to know now, what can i do, aside from chains, to get better traction when it snows? i already run 500 lbs in the back over the axle but still get one wheel action alot. im not complaining about it, i know what i bought and what it does, but want to do what i can to improve this so i can enjoy my truck more

Re: Rear gear question
 

Theres a big difference between lockers and posi-traction units. I have posi units in both of my 72 C-10's and like you I live where the snow inevitably gets deep. The posi unit will not change your mileage and is smooth through turns in slick conditions. A locker will slide one wheel where a posi will not. Unless I'm drag racing or off roading would I even consider a locker. Once more, the posi is a preferred unit in many off road applications. You have to remember, years ago before every other vehicle on the road was a so called 4X4, farmers and country folk ordered posi's in their all terrain trucks. The newest vehicle in my fleet is a 91 Jeep Cherokee and when in 4H, you still only have two tires locked in, one front, one rear...Mighty hard to beat a Eaton Posi on and off the road...I'll add this as well, I pulled a floating 3:08 out of my work horse C-10 and stuck a new 3:73 Eaton Posi unit in it, 350TB tranny (Heavy Duty) and my mileage only went down from 13mpg to 11mpg respectively...The pulling ability felt like an instant 50 HP...That was the gearing not the posi unit...The cool thing about a posi is, it only engages when one or the other wheel begins to loose traction...My .02 cents ~Ghostrider~

Re: Rear gear question
 

x2!

Re: Rear gear question
 

12mpg is not bad. My '83 K20 used to get 14 or so with 700R4 and 3.42 gears. If you are not going to go to overdrive, I would change to 3.73 or 3.55. That should be plenty of gear for hauling and should help slightly with mileage. A more tangible benefit should be fewer RPMs at cruising speed which may be quieter inside the cab.

Re: Rear gear question
 

I've read and didn't see, but do you have the Eaton axle or the Dana 60? If you have the Eaton, you are SOL on a limited slip aka Posi-traction. But posi is the answer you are looking for if you have the Dana axle. The cheapest way to do that is a TrakLok in a Dana 60. Not known for really good longevity, based on what you are doing should still be good for 10 years and it could be rebuilt. Figure $300 to buy it if you shop around and another couple of hundred to install it.

Re: Rear gear question
 

This is my set up on my BB, just added the eaton posi and changed the gear to a 3.73 from a 3.08 in a non Dana rear end. I like it..

Re: Rear gear question
 

I have a Dana 60 rear end with 4.10 gears. Any recomended places to buy a traklok ?

Re: Rear gear question
 

Check out the eaton truetrac. Lots of good info on Eaton's website.

Re: Rear gear question
 

The TrueTrac is a great choice as well. I like Randy's Ring & Pinion but any of the big mail order places should be able to fix you up.

Re: Rear gear question
 

looking at different ones online i found this one
http://www.ebay.com/itm/GM-12-Bolt-T...a0e292&vxp=mtr

idk if i got the link posted right so il try it and see. would this one here fit then? it seemd to match up but want to make sure i didnt overlook something

Re: Rear gear question
 

Nope. That's for a 12 bolt. You need one for a Dana 60 with 30 spline axles. Here are some choices.

The PowerLock is real beef:
http://www.ebay.com/itm/DANA-60-POWE...342a33&vxp=mtr

Here's a TracLock with bearings and bolts and shims:
http://www.ebay.com/itm/OEM-DANA-60-...4b0c83&vxp=mtr