What Rear End Do I Have?

[El Camino Man]

Hey guys. Im new to Chevy trucks and am trying to get everything figured out on mine. The details of my truck are in my sig.

I read on here duallies came with either a 14 bolt FF or a D70. How can I tell them apart?

Also, whats the benefits/differences of each?

And how can I tell if its a posi or not? I know most come with a tag that states something about adding limited slip fluid.

All info is appreciated!

 

[bucket]

Single rear wheel trucks and the narrow (cab&chassis) duallies got the GM 14bolt axle. Regular duallies like yours (bed and fenders) got the Dana 70 rear axle. It's probably an open rearend, I don't think GM ever used a locker of some type in the D70, but someone please correct me if I'm wrong.

 

[El Camino Man]

I don't believe its a posi either. I dropped the clutch on some gravel the other day and it looked like it only spun one side. I was disappointed

 

[anubisani]

Single rear wheel trucks and the narrow (cab&chassis) duallies got the GM 14bolt axle. Regular duallies like yours (bed and fenders) got the Dana 70 rear axle. It's probably an open rearend, I don't think GM ever used a locker of some type in the D70, but someone please correct me if I'm wrong.

I think mines has a locker when I do burnouts it leaves 4 foot prints on the pavement

 

[El Camino Man]

I may have to try spinning my tires again to know for sure. A locker is pretty expensive...

 

[HotRodPC]

I may have to try spinning my tires again to know for sure. A locker is pretty expensive...

If you're running stock tire and stock motor for the most part, you can get by with a Lock Right for less than $400. Called a lunchbox locker. You can probably install that yourself. In short, take out your spider gears and install the locker parts in their place. No re-setting up of the Ring and Pinion. With your full floating axles, you won't even have to jack the truck up to install it.

Pull your axles out. Remove the rear cover. Pull your spider gears out, install the lunchbox, push the axles back in, replace the cover, fill with oil. Drive it around the block a couple times, then do a 4 wheel burnout.

 

[El Camino Man]

So thatd be a mechanical locker right? How are those on reliability?

 

[HotRodPC]

So thatd be a mechanical locker right? How are those on reliability?

Yes, it's a mechanical locker. If you have quiet exhaust, they are noisy too on turns. You'll hear it ratcheting. I've heard for a stock motor or up to 300hp, and up to a 33in tire, they are fairly reliable. They're not as strong as a Detroit Locker or ARB air locker but I know of 2 people that have them in stock OE trucks and they are holding up well.

 

[El Camino Man]

Sounds like a winner for me lol. I wont do a lift and tires since its 2wd and I MIGHT do a turbo later on down the road but I doubt ill be over 300hp. Thanks for the info!

 

[marks86]

a m1028a3 which was a single rear wheel converted to a dually by the military had a detroit locker d70

case anyone was woundering

 

[El Camino Man]

Quick question for ya guys. Theres 3 versions of the D70. The regular one, a D70HD and a D70U. Which one is mine?

And also, Iv been looking around for some info and pricing on one of those lunchbox lockers. I read where several people have used them and like them but I cant find any info on them otherwise

 

[bucket]

I'm not sure of the differences, but I've always been told that Chevy used the D70HD in the dually trucks.

 

[El Camino Man]

Thanks! Just another tid bit of info for ya guys:

According to JP Magazine (a jeep mag), the D70HD is rated as a stronger axle than a ROCKWELL! It got top 3, only losing to a D80 and D135. Hard to beat a 35 spline lol.

Wanna guess what got 4th? FF 14 Bolt

Then 5th was the Rockwell...

 

[El Camino Man]

Anyone have a link to a lunchbox locker? Anyone?

 

[HotRodPC]

Anyone have a link to a lunchbox locker? Anyone?

Here's the cheapest I've ever seem the Lock Right and the No Slip.

http://www.rocky-road.com/powertrax.html