Welded front diff question

Cash214 · December 2, 2019

I’m wanting to have a front locker in my 2015 Sierra 1500. If I can just weld the gears that would be even better because Im a on a tight budget but I am a good welder.

From my research and understanding it seems like the front differential has a disconnect so that in 2wd a locker (or welded gears) in the front wouldn’t make a difference. It would only be noticeable when the center axle disconnect is engaged due to 4wd being engaged. Does this sound correct and does anyone have experience with this?

Also its on 35s and I know that the strength or the front end isn’t great and I would have to be very careful with a locked front end. This is also a daily driver but it seems like this would not effect anything while in 2wd.

Snowcamo · December 2, 2019

I don't think it makes a diff wheither front or back. If its welded to rotate both wheels it will chirp/ skip in turns.

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SierraHD17 · December 2, 2019

It's going to pull to the drivers side. With it locked and the passenger axle disconnected as it does you still will have load spinning the front driveshaft constantly on the drivers side that normally would just go the path of least resistance to the disconnected passenger axle. Since the carrier is locked to the drivers axle side it and the driveshaft will always spin where it normally wouldn't. Guys have been trying this since 1988 and it's not pleasant.

SierraHD17 · December 2, 2019

2 minutes ago, Snowcamo said:

I don't think it makes a diff wheither front or back. If its welded to rotate both wheels it will chirp/ skip in turns.

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It won't. Passenger axle has a collar that connects the inner and outer portion. In 2wd it disconnects so the passenger side freewheels. It will however pull to the drivers side.

In 4wd it will hop and skid.

Cash214 · December 2, 2019

Just now, SierraHD17 said:

It won't. Passenger axle has a collar that connects the inner and outer portion. In 2wd it disconnects so the passenger side freewheels. It will however pull to the drivers side.

In 4wd it will hop and skid.

So in 2wd it will pull to driver side? Can you explain why? I don’t know a ton about differentials but I have a basic understanding. Why would it have a load spinning the front driveshaft? Does the open diff in the front allow the wheel to spin while the driveshaft doesn’t and then a locker would make the driveshaft and driver wheel locked together?

Cash214 · December 2, 2019

I understand how it would operate in 4wd and have no issue with that, it’s just the 2wd operation I’m trying to understand.

SierraHD17 · December 2, 2019

Your passenger wheel hub is freewheeling with zero resistance other than the bearing. The drivers side is turning the gears and the driveshaft putting drag on it. Yes it will pull to the drivers side.

When it's open all you spin is the spider gears and that disconnected passenger side axle....and not the entire gear set, front driveshaft along with the transfer case input shaft.

How noticeable will it be on your truck? Do it and let us know lol.

Edited December 2, 2019 by SierraHD17

Cash214 · December 2, 2019

2 minutes ago, SierraHD17 said:

Your passenger wheel hub is freewheeling with zero resistance other than the bearing. The drivers side is turning the gears and the driveshaft putting drag on it. Yes it will pull to the drivers side.

When it's open all you spin is the spider gears and not the entire gear set and front driveshaft.

Thank you. Do you know how hard it would pull? I wouldn’t think it would be very bad but I don’t have experience with it. And couldn’t you align it to pull to passenger side slightly to compensate?

asilverblazer · December 2, 2019

Welding up the differential is something you do on a 20 year old mud truck, not a 4 year old daily driver.

You will regret it.

Drivability will suffer as noted above, plus, whatever you are doing with 35" tires that warrants a locked front axle is going to result in other far more significant failures. If your funds can't afford a proper locker, then they won't support the magnitude of repairs you will encounter either.

SierraHD17 · December 2, 2019

He can't even get an actual locker or limited slip of any kind for the 8.25" front as far as I know. There is nothing available as they are so weak they can't handle it. The 9.25" has a couple options but that's it.

flyingfool · December 3, 2019

for the rear

https://eastcoastgearsupply.com/i-20655114-gm-9-5-14-bolt-powertrax-lock-right-1950-lr-all.html

some people also fill the carrier with a bunch of lead and melt it into the spider gear housing, theres lots of cheap lead in dead old car batteries, this is reversable, just remelt the lead from housing

Edited December 3, 2019 by flyingfool