Rear Locker, Good idea?

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DeiselRed
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Rear Locker, Good idea?

Post by DeiselRed »

Hey guys :wave: I have a 7.625 10bolt 28 spline rear diff without gov-lock and I was wondering what your input would be on installing a locker? I have been looking around and I think the Powertrax No-Slip would be my best bet. I have heard alot of good reviews on them and I was wondering what your input would be on picking on of these up. Any opinions would be great! Thanks!


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HenryJ
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Re: Rear Locker, Good idea?

Post by HenryJ »

Powertrax lock-right is fine offroad, but a big mistake for a daily driven street vehicle, IMO. Do a quick search and you will learn from the mistakes that I made.

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Re: Rear Locker, Good idea?

Post by killian96ss »

I would get a Detroit Tru-Trac gear driven differential. They are always active splitting torque to both wheels, and they don't violenty engage like the Eating Gov-Loc. I have one in my track driven SS and my 88 S10 4x4 Blazer. The Tru-Trac is excellent on road as well as off!

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Re: Rear Locker, Good idea?

Post by DeiselRed »

Awsome... I will deffinatly look into the tru-trac....Did you buy any other parts for the rear end before you installed it or just the unit itself?
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Re: Rear Locker, Good idea?

Post by killian96ss »

DeiselRed wrote:Awsome... I will deffinatly look into the tru-trac....Did you buy any other parts for the rear end before you installed it or just the unit itself?
I used a complete installation kit (bearings, races, shims, seals, marking compound, carrier bolts, crush sleeve, etc), but I also put in new gears. If you are just swapping carriers I would use new carrier bearings, new ring gear bolts, and be sure to check the backlash with a dial indicator mounted on a magnetic base. It is also important to make sure the carrier bearing caps go back on the same exact way they were removed.

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Re: Rear Locker, Good idea?

Post by HenryJ »

Good used bearings can be used sometimes. These are tapered roller bearings and as long as they are not excessively worn or pitted to any extent, they will function no differently than new. The shims preload them on the carrier. There is no difference between setting up new or used bearings. Many times a used differential and bearings can be swapped in and line up perfect. Especially when using the matched pinion. I have done this more times than I can count in the fleet. Drop them in torque to spec , check the clearances and pattern. Lots of times they have swapped in easily and saved lots of time and money.
Installing a new differential use new bearings. That is just common sense. Now that being said you really need a machined set of bearings to set up the ring gear. Pulling a bearing to set the shim pack will likely damage a pressed on bearing. The machined set of bearings are clearanced to slide on and off for set up. These are new, so new bearings must be used to match the settings.

The G80 does not engage harshly. It uses a gear drive to smoothly engage clutches locking the differential. That is the Powertrax Lockright that does that. It uses hardened teeth to engage the axles. They pop and disengage violently if they are under load. If your G80 engages or disengages harshly the clutches are stuck or you have other problems. This may be from using the wrong fluid and damaging the clutches, or other failed parts.

IMO, the G80 is a good differential for a daily driver. Their street manners are very good and the locking power of their system is unmatched in a limited slip differential, due to the design. Any differential can go bad and there have been G80 failures, just as many others have failed too. These are usually under severe conditions. Would I choose a G80 for racing? No! It is not designed for that. Heck it is designed not to engage at higher speeds. That is why there is a fly weight to disengage the locking pawl. For racing or hard core duty I would make another selection depending upon the application and needs.

Detroit is a good differential. I will not fault that. I have not used their Trutrac differential, but I will assume it is of a good quality and probably functions much like a Auburn and other limited slip clutch type differentials. I have a Detroit locker in my Vega and a Tracloc in the HenryJ. I have installed quite a few Auburns in street rods. The Detroit lockers are very popular. I can' t count the number of those I have installed.

Keep in mind that installing a new differential is not going to be cheap. If you can do it yourself it will still be about $600 for parts by the time you buy seals, gasket, bearings, shims, crush sleeve, nut and bolts. If you are building the flexy stock axle you need to upgrade the cover to support it , as well as improve the carrier bearing and axle bearing lubrication. That means you need a support cover. If you are paying to have this done plan on about $800-$1000 total cost. Now what is the next weak link? I am currently worried about the strength of the pinion bearing shims and axle bearings on the small 10 bolt axle that we have.

Why are you dumping this much into a small differential? If you are going to this much expense why not upgrade to a 8.5" - 8.625" differential. Bigger axles, bearings, and case. That would be something worth investing in a good carrier like a Detroit.

I think if you are going to stay with the stock 7.625" rear axle and want a locker in the back, buy used and be happy with a G80. You can buy one most places for under $125. Installed yourself under $200. Having it all done should be under $400.
If you want more and a nice heavy locker out back, go with the upgrade to a ZR2 rear end. If you are on a budget, use the stock G80 until you decide to upgrade some day.

Summary: I see these choices.
#1 Buy a used G80 differential and upgrade your stock differential. $400
#2 Go one step better and install a Detroit with a support cover. $800
#3 Install a used ZR2 8.625" rear axle assembly with G80 $750

There is no one answer for everyone. Each will need to decide how they are using the vehicle, the modifications made to it , their budget, how long they intend to keep it.

What ratio is your truck with the open carrier?

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Re: Rear Locker, Good idea?

Post by rlrnr53 »

We used to have a C-3500 shop truck with a Detroit locker in it. It could be a handfull to drive. The worst thing about it was at times it would lock up with no warning. I have had ti lock up so hard that I stopped and got out of the truck thinking that I had been resr ended. This would happen quite regularly, but usually not as violently. But when itlocked up, I think athat truck would have climbed a telephone pole.
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HenryJ
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Re: Rear Locker, Good idea?

Post by HenryJ »

rlrnr53 wrote:We used to have a C-3500 shop truck with a Detroit locker in it. It could be a handfull to drive.
That is exactly the reason that the G80 Eaton GovLoc does not lock at higher speeds. You don't want to go sideways on ice at highway speeds. Spinning one tire at speed is safer.
I like the fact that I don't have to warn / teach my wife to drive the truck with a locking rear differential. It is smart enough to know that when the vehicle is moving at speed it doesn't need to be locked.

"Speed doesn't kill, suddenly becoming stationary does." - Richard Hammond
"Speed is just a matter of Money - How fast do YOU want to go?"-Mechanic from Mad Max-
If at first you don't succeed - Don't take up Skydiving!
- ThunderII KE7CSK