Locker for 2wd

Here is what I would do.
I would find a 9.5” semi-float rear - 6 lug
I would install an Eaton Detroit TrueTrac
I would install 4.56 gears
I’d also install the conversion U-joint so you can keep your driveshaft. There are write-ups on this conversion.

For the front I would install light duty C2500 (6-lug) brakes that way my wheels would match. There are write-ups on this conversion.

Couldn’t he swap in a 5 bolt 70s Chevy 12 bolt from a pickup? Not use on the spring width of the square body vs OBS?? Someone should know

fancyTBI said:

Here is what I would do.
I would find a 9.5” semi-float rear - 6 lug
I would install an Eaton Detroit TrueTrac
I would install 4.56 gears
I’d also install the conversion U-joint so you can keep your driveshaft. There are write-ups on this conversion.

For the front I would install light duty C2500 (6-lug) brakes that way my wheels would match. There are write-ups on this conversion.

Click to expand...

Why not a full float? I do like the idea of the 4.56. I now know why I didn’t have traction when I drove it in the snow a few years ago. Because I didn’t let it spin long enough to get it to lock the diff. And searching for a used 14 bolt sf or ff is proving to more difficult than I thought. I haven’t checked the classifieds here yet though.

@fancyTBI has the perfect plan IMO.

The 9.5” semi floater is a very tough axle. No need for the 10.5”, plus the 10.5” have 8 lug axles so you’d be super mismatched.

To testify to the 9.5” strength.
I have a 6 lug 9.5” 14bolt in my stick shift swapped Tahoe with a very healthy LS motor and it has seen hundreds of 6,800 rpm clutch dumps. One time I pulled an Amazon van out of a sandy road and snatched it so hard with a kinetic rope it picked the back of my Tahoe up and destroyed the seat bar endlinks. Rear end has never needed any repairs.

The reason to look at the 6 bolt semi floater 14 bolt vs the full floater 8 bolt is mostly the wheel bolt pattern and the fact that the Center of the axle sticks out unlike the semi.

Gotcha. Yeah I’ve been researching the 14b sf and seems like that’s a very common swap in our trucks. So common I have yet to find one for sale let alone at a decent price near me. I found one in a rolling chassis 4x4 plus the cab near me for $150. But I don’t have anywhere to store the frame. I did ask to buy just the rear 14b. So I’ll see what he says.

AmericanPatriot100 said:

Why not a full float? I do like the idea of the 4.56. I now know why I didn’t have traction when I drove it in the snow a few years ago. Because I didn’t let it spin long enough to get it to lock the diff. And searching for a used 14 bolt sf or ff is proving to more difficult than I thought. I haven’t checked the classifieds here yet though.

Click to expand...

FF is 8 lug and more effort than it’s worth to convert it to 6 or convert the front to 8.

I have a SF in both my 2500s. They are durable except for the G80. I just had my C2500 rear end gone through and replaced the G80 with an Eaton unit. So far I’m very happy.

2wd options
put lots of weight in the bed,.
carry tire chains,.
buy a 4 wd

With a 2WD truck in snow/ice ^^^^^already mentioned it comes down to the type of tires (including profile/size) and added weight over the rear axle. I would add feathering the pedal for maximum grip on takeoff is important to get it to engage quicker assuming the engine and transmission is a stock setup and running well. Any drivability issues i.e. accelerator response may impact when and if it locks. I believe the G80 installed on trucks engages when there is a diff of approx 75-120 RPM between the rear wheels. The trucks are a mechanical lock G80 and not a limited slip used with cars. No additives (i.e limited slip gear lube) should be used as it may cause a delay in the locking mechanism. Most of the old trucks (including mine when purchased) may be filled with the incorrect gear lube due to the confusing nomenclature, contaminated fluid and/or worn clutches all causing serious operational issues. Have you dropped the cover? Check to make sure your truck is locking properly and change the fluid if you are uncertain of what’s in there. 80W-90 GL5 or 75-90 GL5. If you go aftermarket you’ll have more choices (clutch, helical gear and torsen-type). How you intend to use your truck will dictate which locker is best for your application. If you’re mainly on the street with light off road, the stock G80 is a good all around choice. My C2500 (8 bolt) has the OEM G80 w/3.73 that I rebuilt and aggressive tires (stock size). Works great in the winter w/weight over the rear axle. No off road or standing burnouts so it works fine for me. If your truck has the 3.73 and larger tires moving to a 4.56 or better is a must if you want some of that acceleration back. This all depends on your budget of course.

Great historical review on differentials up to the Eaton Locker.

Retro Eaton G80 video - love watching these pitches

Locker Comparison video

fancyTBI said:

FF is 8 lug and more effort than it’s worth to convert it to 6 or convert the front to 8.

I have a SF in both my 2500s. They are durable except for the G80. I just had my C2500 rear end gone through and replaced the G80 with an Eaton unit. So far I’m very happy.

Click to expand...

Sorry to get off topic, but did you ever kill a g80 in a 9.5”? Mines acting funny but not dead yet and still locks up in dirt.