The value of a locking differential

jkust

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I got an up close example of the benefit and value of a locking differential. My neighbor's friend backed his truck to retrieve a trailer just past the snow bank so that the passenger side wheels were in the snow and the drivers side wheels were still on pavement. The truck was a 4x4 Chevy Silverado from the early 2000's but had no G80 locking differential. I wasn't suprised to see both of the passenger side wheels on the snow spin him into deeper and deeper trouble while the two wheels on the dry pavement sat there receiving no power. It was a shining example of how silly it is to not pay the extra $150 for the locking differential option when buying a truck new. His 4 wheel drive was rendered useless because of the open differentials doing a really mundane task and never got near the trailer.
 

chaffinyo

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Re: The value of a locking differential

I have to agree with you on that, I have posi lock in the back, so i can/have gone places that "normal" 2wd truck could not, just the same you cant rely on posi trac because it wont always lock both wheels in
 

jkust

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Re: The value of a locking differential

I have to agree with you on that, I have posi lock in the back, so i can/have gone places that "normal" 2wd truck could not, just the same you cant rely on posi trac because it wont always lock both wheels in

Yep there is a big difference between the GM G80 Locker and the G86 limited slip. I have one of each. Driving in the winter with a full locker takes some getting used to if you don't have a stabilitrac system (as in one of my prior SUV's) because when you go around a corner and it locks up, the rear wants to pass the front which is really exacerbated on ice during a normal MN winter. The stability control absolutley won't let the rear pass the front no matter how hard you try as in both our current suv's. If your tires aren't up to par it is downright dangerous without stabilitrac and with a locker. Taking that to the boat ramp then you can get away more often than not, not even using your 4wd if you have a locker. They cost almost nothing as a factory option but are a huge pain to have installed after the fact. Take away the locker and only a 2wd truck as rare as that is here in MN I do still see it and those are Youtube moments at the ramp.
 

ricohman

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Re: The value of a locking differential

The GM 80 is not much up on a limited slip and when the weights fly apart it doesn't work at all. I've repaired lots and they simply don't last under a heavy foot.
A real locker, like and ARB, will turn both wheels all the time when engaged. I've used ARB's at both ends for over a decade and while expensive, you get what you pay for.
 

dingbat

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Re: The value of a locking differential

I'm having a hard time understanding why anyone would buy a truck up north and not have 4WD. You couldn't give a 2WD truck away around here.
 

tomdinwv

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Re: The value of a locking differential

My Dodge Ram (4WD) has limited slip in the rear end and I like it. I hardly ever have to kick in the transfer case to get where I need to go. I didn't even think about it when I bought the truck, it just happened to be equiped with it. I will not buy another with out it.
 

bruceb58

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Re: The value of a locking differential

I have asked this question before but will ask again. I have a 2WD 2000 1/2T Silverado that my dad bought new with no limited slip. If I was to change to a limited slip/locker diff, what would be the reccomended one to get?
 

ricohman

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Re: The value of a locking differential

I have asked this question before but will ask again. I have a 2WD 2000 1/2T Silverado that my dad bought new with no limited slip. If I was to change to a limited slip/locker diff, what would be the reccomended one to get?

Depends what you have for a diff.
If you are going to a limited slip you will need a new carrier. You can install an aussie locker in your present 10 bolt. If you install a limited slip (and GM calls its limited slips posi, lockers ect) you will have to accept that if one tire is off the ground you won't be going anywhere. The aussie will give you outstanding traction all the time even if one tire is in the air, but it will ratchet and clunk and lower speeds when turning.
I would go with a high quality after market limited slip for a street truck. You can remove and install the ring gear or swap gearing. Its up to you.
I would stay away from the eaton variety GM80 or anything govloc.
 

bruceb58

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Re: The value of a locking differential

My main issue is when I am trying to get up a driveway with a little snow on it. Don't really want to put chains on to go up 20 feet. I have no problems with launch ramps.
 

tswiczko

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838
Re: The value of a locking differential

I have asked this question before but will ask again. I have a 2WD 2000 1/2T Silverado that my dad bought new with no limited slip. If I was to change to a limited slip/locker diff, what would be the reccomended one to get?

I had a G80 grenade on me (after 170k miles)
Got another off ebay for 20 bucks + shipping, and rebuilt my rear end ( shims bearings seals ring and pinion) for less than $300.
If I had the money at the time I would have gotten an Eaton Tru Trac (no clutches)
 

ricohman

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Re: The value of a locking differential

My main issue is when I am trying to get up a driveway with a little snow on it. Don't really want to put chains on to go up 20 feet. I have no problems with launch ramps.

Traction in the rear will make the truck want to slip side to side in that situation if there is any slope.
I would go with a limited slip for a street truck. And you can find them as new take offs.
 

jkust

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Re: The value of a locking differential

The GM 80 is not much up on a limited slip and when the weights fly apart it doesn't work at all. I've repaired lots and they simply don't last under a heavy foot.
A real locker, like and ARB, will turn both wheels all the time when engaged. I've used ARB's at both ends for over a decade and while expensive, you get what you pay for.

Agreed, the Eaton G80 locker that GM uses is effective but they have a bad rep for imploding. Not terribly expensive to fix in this age of a million here and a billion there but why should you have to.

Depends what you have for a diff.
If you are going to a limited slip you will need a new carrier. You can install an aussie locker in your present 10 bolt. If you install a limited slip (and GM calls its limited slips posi, lockers ect) you will have to accept that if one tire is off the ground you won't be going anywhere. The aussie will give you outstanding traction all the time even if one tire is in the air, but it will ratchet and clunk and lower speeds when turning.
I would go with a high quality after market limited slip for a street truck. You can remove and install the ring gear or swap gearing. Its up to you.
I would stay away from the eaton variety GM80 or anything govloc.

GM does a bad job of calling a locker a limited slip and a limited slip a locker in literature or at least the industry does. You need to look at the glove box code to see what you actually have. A G80 Eaton Locker's purpose among others is that when one tire is off the ground you will go somehwere however their G86 RPO code, Limited Slip, is different and indeed more for street trucks than off road. The G86 doesn't lock the wheels giving you benefit in low traction situations but not to the same extent as a full locker. There are lots of nice youtube videos comparing a lsd to a locker to an an electronic version of an lsd. The locker seems to always perform the task best.

Also then a lot of the trucks that I know where the person bought it used and realized later that it had no locker also tended to have the base 3.42 gear ratio as opposed to the 3.73 more apt for towing and so a full swap replacing the entire axel front and rear with the 3.73 from a salvage yard was more cost effective than buying a locker and having someone put it in or so I understand.


dingbat said:
Re: The value of a locking differential
I'm having a hard time understanding why anyone would buy a truck up north and not have 4WD. You couldn't give a 2WD truck away around here..

I couldn't agree more, If you left it running in the wrong part of town I don't think even a car thief would take one here in MN. When I see a 2wd truck or even an suv my assumption is the owner is a transplant from somewhere warmer than MN. When I see them for sale on CL, there is always some half hearted attempt to explain why a 2wd is less costly to fix or something to try to offload it. Suprisingly a 3.73 and a locker is hard to find on some suv's as I learned with my most recent suv hunt. 4wheel drive is an insurance policy you may never need but secretly hope you do.
 

Lou C

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Re: The value of a locking differential

I got an up close example of the benefit and value of a locking differential. My neighbor's friend backed his truck to retrieve a trailer just past the snow bank so that the passenger side wheels were in the snow and the drivers side wheels were still on pavement. The truck was a 4x4 Chevy Silverado from the early 2000's but had no G80 locking differential. I wasn't suprised to see both of the passenger side wheels on the snow spin him into deeper and deeper trouble while the two wheels on the dry pavement sat there receiving no power. It was a shining example of how silly it is to not pay the extra $150 for the locking differential option when buying a truck new. His 4 wheel drive was rendered useless because of the open differentials doing a really mundane task and never got near the trailer.


I agree with the need for 4x4 in any areas that get snow, but back in the day one of the tricks we did use to get 2 wd cars with no limited slip going in snow (one wheel on snow, other on dry) was as follows: gradually engage emergency brake, with the release handle pulled out while applying a bit of power. Braking the spinning wheel will send the power through the open diff to the side with traction and hopefully that will get the vehicle to move. I drove full size GMs back then, 5.7 V-8s, studded snows and a few sand bags in the trunk. All open diffs.
 

ricohman

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Re: The value of a locking differential

Agreed, the Eaton G80 locker that GM uses is effective but they have a bad rep for imploding. Not terribly expensive to fix in this age of a million here and a billion there but why should you have to.



GM does a bad job of calling a locker a limited slip and a limited slip a locker in literature or at least the industry does. You need to look at the glove box code to see what you actually have. A G80 Eaton Locker's purpose among others is that when one tire is off the ground you will go somehwere however their G86 RPO code, Limited Slip, is different and indeed more for street trucks than off road. The G86 doesn't lock the wheels giving you benefit in low traction situations but not to the same extent as a full locker. There are lots of nice youtube videos comparing a lsd to a locker to an an electronic version of an lsd. The locker seems to always perform the task best.

Also then a lot of the trucks that I know where the person bought it used and realized later that it had no locker also tended to have the base 3.42 gear ratio as opposed to the 3.73 more apt for towing and so a full swap replacing the entire axel front and rear with the 3.73 from a salvage yard was more cost effective than buying a locker and having someone put it in or so I understand.




I couldn't agree more, If you left it running in the wrong part of town I don't think even a car thief would take one here in MN. When I see a 2wd truck or even an suv my assumption is the owner is a transplant from somewhere warmer than MN. When I see them for sale on CL, there is always some half hearted attempt to explain why a 2wd is less costly to fix or something to try to offload it. Suprisingly a 3.73 and a locker is hard to find on some suv's as I learned with my most recent suv hunt. 4wheel drive is an insurance policy you may never need but secretly hope you do.

The biggest problem with the eaton govloc is that you need some wheel speed to engage it. Thats why they are nearly useless rock crawling. You can't ease over anything as it engages with a bang.
I would never regear with anything under 4.10. My last Super Duty was ordered with 4.30's.
 

Mike Zee

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Re: The value of a locking differential

I ran a 2wd Chevy w/t for 9 years. In those 9 years I only had 1 occation where I wish I had 4wd. I would absolutely buy another in the future. For winter a little weight in the back, good tires, locking diff, no problem. The way trucks are priced now I have been looking at them. I have never had to use my 4wd to pull my boat out. Actually the 4wd didn't work in the F150 for 3 years, just kept forgetting to get it fixed. Only fixed it getting it ready to trade in. I would not have a 2wd without a locker of some type because without one, you will get stuck in the weirdest ways. Our weather isn't that bad anymore around here, when it is they seam to get after it ok.
 

DuckHunterJon

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Re: The value of a locking differential

If only for occasional use, I'd go with an air locker (like ARB). Drives just as it does now, but when you need it, hit a button and it's fully locked. I've had them in the fronts of 2 trucks (with G80's in the rear) and they really are a great addition.
 

jkust

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Re: The value of a locking differential

The biggest problem with the eaton govloc is that you need some wheel speed to engage it. Thats why they are nearly useless rock crawling. You can't ease over anything as it engages with a bang.
I would never regear with anything under 4.10. My last Super Duty was ordered with 4.30's.

The offroad guys I know like the g80 for its effectiveness. It locks with a 100 rpm difference which is quick but yes they tend to have a rep for imploding for the offroaders. I don't know of any daily drivers that have had the issue prematurely which to me is under 100k miles.

I agree with the need for 4x4 in any areas that get snow, but back in the day one of the tricks we did use to get 2 wd cars with no limited slip going in snow (one wheel on snow, other on dry) was as follows: gradually engage emergency brake, with the release handle pulled out while applying a bit of power. Braking the spinning wheel will send the power through the open diff to the side with traction and hopefully that will get the vehicle to move. I drove full size GMs back then, 5.7 V-8s, studded snows and a few sand bags in the trunk. All open diffs.

In my 30's but started driving on all 1970's cutlass supremes, rwd, open diffs, and low hp v8's and we just figured it out with a little left foot braking similar to your story but all of our e brakes were rusted solid.

I ran a 2wd Chevy w/t for 9 years. In those 9 years I only had 1 occation where I wish I had 4wd. I would absolutely buy another in the future. For winter a little weight in the back, good tires, locking diff, no problem. The way trucks are priced now I have been looking at them. I have never had to use my 4wd to pull my boat out. Actually the 4wd didn't work in the F150 for 3 years, just kept forgetting to get it fixed. Only fixed it getting it ready to trade in. I would not have a 2wd without a locker of some type because without one, you will get stuck in the weirdest ways. Our weather isn't that bad anymore around here, when it is they seam to get after it ok.

Have truly needed my 4x4 at least a few times each year (ignoring the constant use of the AWD feature in the winter) getting out of difficult ramps usually on vacation, on a tuesday when nobody would be around to help me out had I gotten stuck with no front wheels to help me out. Pulling my 4000+ tiny 18 footer out of the water sometimes at a sand ramp would be literally impossible without 4x4. Maybe a lighter boat but 2+tons with only rears would be if nothing else fun to watch if it wasn't me.
 

cyclops2

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Re: The value of a locking differential

A true POSITRACTION rear end does everything possible correct all the time. American or for the last few cars Japanese.

Smooth as silk . Cornering on 1/2 ice / oil or anything else is a no problem. I have had good units.
 

ricohman

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Re: The value of a locking differential

The offroad guys I know like the g80 for its effectiveness. It locks with a 100 rpm difference which is quick but yes they tend to have a rep for imploding for the offroaders. I don't know of any daily drivers that have had the issue prematurely which to me is under 100k miles.


In my 30's but started driving on all 1970's cutlass supremes, rwd, open diffs, and low hp v8's and we just figured it out with a little left foot braking similar to your story but all of our e brakes were rusted solid.



Have truly needed my 4x4 at least a few times each year (ignoring the constant use of the AWD feature in the winter) getting out of difficult ramps usually on vacation, on a tuesday when nobody would be around to help me out had I gotten stuck with no front wheels to help me out. Pulling my 4000+ tiny 18 footer out of the water sometimes at a sand ramp would be literally impossible without 4x4. Maybe a lighter boat but 2+tons with only rears would be if nothing else fun to watch if it wasn't me.

Nobody I off road with would use a G80 for anything. Light duty parts and I have seen dozens of them fail. Pile of junk if you are rock crawling. We all run ARB's or Detroits though. You can't run up the side of a 4 foot boulder with a G80. Well, you could but the diff won't survive.
Besides, they fling their guts all over when you run anything bigger than 33 inch tires. I haven't seen any trucks running them for many years now and there's good reason for that.
Now they will survive in a street truck and at the boat ramp. They just don't cut it on Hal Jons or the Ice Man trails in S.D.
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No govloc here!
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If you want ultimate strength, nothing beat mog portals.
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ricohman

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Re: The value of a locking differential

I agree that a well set up limited slip is all you need for a street truck. I run two of them in my F350.
 
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