Eaton Differentials - Which one?

DenaliHD66

Original poster
Member
Dec 4, 2011
597
I'd love to get a locking diff, limited slip blows. I'm not sure if the ones I'm mentioning are going to be compatible with our trucks or not, but I was looking at the Eaton MLocker Diff, which is a limited slip axle, then engages when wheel spin is 100rpm difference. The other I was considering was NoSPIN Diff, where it puts down power to both wheels 100% of the time, and unlocks when turning.

I think I'd lean towards the first one, because I'm going to be doing mostly on-road driving and I have a feeling the latter wasn't really designed to be used that way. Anyone have any thoughts or care to confirm that these would fit my (I believe 8.6" axle) Envoy XL?
 

ScarabEpic22

Member
Nov 20, 2011
728
Just to let you know, right now you have a locker, not a LSD. The only GMT360/370/305s that have LSDs are the TBSS and 9-7X Aero. All I6s and 5.3s are paired with a G80 locker, not the G86 LSD the SS/Aero comes with.

Cant help you on your options, I havent had a need to upgrade either of mine yet. Have the G80 in my 02 I6 and of course the G86 in the SS.
 

fishsticks

Member
Nov 21, 2011
433
DenaliHD66 said:
I'd love to get a locking diff, limited slip blows. I'm not sure if the ones I'm mentioning are going to be compatible with our trucks or not, but I was looking at the Eaton MLocker Diff, which is a limited slip axle, then engages when wheel spin is 100rpm difference. The other I was considering was NoSPIN Diff, where it puts down power to both wheels 100% of the time, and unlocks when turning.

I think I'd lean towards the first one, because I'm going to be doing mostly on-road driving and I have a feeling the latter wasn't really designed to be used that way. Anyone have any thoughts or care to confirm that these would fit my (I believe 8.6" axle) Envoy XL?


First, check your glovebox RPO sticker for code G80. If it's present then you already have the first type of locker you mentioned. If not, you have an "open" differential.

The No-Slip (not No-Spin) is a locker by Richmond Gear. It's basically a fancy version of their Lock Right. I swapped in an 8.6" axle from and EXT after my G80 blew up. I run a No-Slip in it (and a Lock Right in the front diff). It is barely noticeable on pavement. The only giveaway is the rear tires will scrub a tiny bit when making a sharp turn from a stop on wet ground.

If you already have a G80, you'll need a new (open) carrier to install a No-Slip. If you don't have a G80, the No-Slip installs into your existing carrier.
 

Jkust

Member
Dec 4, 2011
946
ScarabEpic22 said:
Just to let you know, right now you have a locker, not a LSD. The only GMT360/370/305s that have LSDs are the TBSS and 9-7X Aero. All I6s and 5.3s are paired with a G80 locker, not the G86 LSD the SS/Aero comes with.

Cant help you on your options, I havent had a need to upgrade either of mine yet. Have the G80 in my 02 I6 and of course the G86 in the SS.

The G80 was an option on Trailblazer, Option on Envoy including Denalis, Standard on Rainier and standard on the 9-7x non aero. Actually only the early Rainier years had it standard then it bacame an option in the last couple years of production. Always standard on the 9-7x non aero. Some of this is up for debate for instance because although the latter year rainiers didn't automatically include it many car sites still carried the 2004 specs over each year which was an error. Not addressing the the G86.
 

ScarabEpic22

Member
Nov 20, 2011
728
Jkust said:
The G80 was an option on Trailblazer, Option on Envoy including Denalis, Standard on Rainier and standard on the 9-7x non aero. Actually only the early Rainier years had it standard then it bacame an option in the last couple years of production. Always standard on the 9-7x non aero. Some of this is up for debate for instance because although the latter year rainiers didn't automatically include it many car sites still carried the 2004 specs over each year which was an error. Not addressing the the G86.

I know, but if you read the OPs first post, he states "I'd love to get a locking diff, limited slip blows." To me, this sounds like he thinks he has a LSD already (which isnt likely if its a stock truck) and wants to swap it for a locker (which if he has either, he has a locker).

Guess I was trying to read between the lines and interpret, cant be right all the time.

The G80 has always been an option, I didnt even know it came standard on ANY GMT360/370/305. I know the only way to get a G86 is an SS/Aero, and its standard on them.
 

DenaliHD66

Original poster
Member
Dec 4, 2011
597
ScarabEpic22 said:
Just to let you know, right now you have a locker, not a LSD. The only GMT360/370/305s that have LSDs are the TBSS and 9-7X Aero. All I6s and 5.3s are paired with a G80 locker, not the G86 LSD the SS/Aero comes with.

Cant help you on your options, I havent had a need to upgrade either of mine yet. Have the G80 in my 02 I6 and of course the G86 in the SS.

Its not standard, its always been an option. I do not have a G80, I looked years ago. It is limited slip, that is what our trucks have. Unless I've been wrong for all of these years? But really, I can spin all 4 on ice, and turning on pavement in 4WD yields crow hopping... open diffs don't do that. I have been in situations where only 2 wheels will spin, and the 2 wheels (1 in front, 1 in rear) that have the most traction don't move at all. That's what an open diff would do, and it would make more sense if I did have open diffs, but still, I thought it was LSD for all of these years.

fishsticks said:
First, check your glovebox RPO sticker for code G80. If it's present then you already have the first type of locker you mentioned. If not, you have an "open" differential.

The No-Slip (not No-Spin) is a locker by Richmond Gear. It's basically a fancy version of their Lock Right. I swapped in an 8.6" axle from and EXT after my G80 blew up. I run a No-Slip in it (and a Lock Right in the front diff). It is barely noticeable on pavement. The only giveaway is the rear tires will scrub a tiny bit when making a sharp turn from a stop on wet ground.

If you already have a G80, you'll need a new (open) carrier to install a No-Slip. If you don't have a G80, the No-Slip installs into your existing carrier.

So do you not recommend the auto mechanical locker, the one that would come standard as a "G80" setup? I see the advantages of having it locked all the time, my only concern was longevity since I'm mostly a road driver, just didn't know how much wear and tear that would be on the gears that let it loose when turning. I didn't know there was a front diff for our trucks. What kind of setup is it? Auto-locking or same setup as rear in that its always engaged?
 

djthumper

Administrator
Nov 20, 2011
14,956
North Las Vegas
DenaliHD66 said:
Its not standard, its always been an option. I do not have a G80, I looked years ago. It is limited slip, that is what our trucks have. Unless I've been wrong for all of these years? But really, I can spin all 4 on ice, and turning on pavement in 4WD yields crow hopping... open diffs don't do that. I have been in situations where only 2 wheels will spin, and the 2 wheels (1 in front, 1 in rear) that have the most traction don't move at all. That's what an open diff would do, and it would make more sense if I did have open diffs, but still, I thought it was LSD for all of these years.

If it doesn't say G80 in your RPO codes you have an open diff, there was no limited slip unless it was added by someone else. But then that changes everything.
 

fishsticks

Member
Nov 21, 2011
433
DenaliHD66 said:
Its not standard, its always been an option. I do not have a G80, I looked years ago. It is limited slip, that is what our trucks have. Unless I've been wrong for all of these years? But really, I can spin all 4 on ice, and turning on pavement in 4WD yields crow hopping... open diffs don't do that. I have been in situations where only 2 wheels will spin, and the 2 wheels (1 in front, 1 in rear) that have the most traction don't move at all. That's what an open diff would do, and it would make more sense if I did have open diffs, but still, I thought it was LSD for all of these years.



So do you not recommend the auto mechanical locker, the one that would come standard as a "G80" setup? I see the advantages of having it locked all the time, my only concern was longevity since I'm mostly a road driver, just didn't know how much wear and tear that would be on the gears that let it loose when turning. I didn't know there was a front diff for our trucks. What kind of setup is it? Auto-locking or same setup as rear in that its always engaged?


You currently have open diffs.


Since you already have an 8.6" open rear axle, it's a no-brainer to go with the No-Slip. You'll spend about $450 on it but it requires NO additional gear setup (a G80 swap would), is way stronger than a G80 and you can install in your driveway in 20 minutes with hand tools.

Install it, run 140w gear oil, and you'll forget it's there until you need it. I run trails in 2WD that some people with open diff's can't do in 4LO.
 

HARDTRAILZ

Moderator
Nov 18, 2011
49,665
fishsticks said:
Install it, run 140w gear oil, and you'll forget it's there until you need it.

Do you run the same in front? What do think is best with the lockers, brand, additives, whatever?
 

DenaliHD66

Original poster
Member
Dec 4, 2011
597
Good stuff guys. No wonder I had such a bad experience under the impression I was running with LSDs haha. Well that NoSlip locker sounds legit then, and I'm interested to hear what works for the front end as well? Is the one you posted from ebay cheaper than Eaton's but just as good? Also do I have the same front diff size as all other GMT 360s, and if so what is it?

Edit: The only thing I don't get, is I thought if they were both open diffs, there wouldn't be any turning friction on pavement at low speeds? Why do I still get the crow hopping then? I understand the front axle is taking a different path than the rear, but even if they are connected, shouldn't they be turning freely? Is it any worse/better with limited slip differentials?
 

Jkust

Member
Dec 4, 2011
946
DenaliHD66 said:
Its not standard, its always been an option. I do not have a G80, I looked years ago. It is limited slip, that is what our trucks have. Unless I've been wrong for all of these years? QUOTE]

You are right only standard on the 9-7x and certain year Rainier's. Our platform (non aero - non ss) had the open diff or the locking not the limited slip. It is what it is. Not that it is the same thing but in the later years of the platform the 4wd and AWD versions came with a traction control that will limit slip as well (earlier years it only came on the 2wd version). That addition coincidently came when the G80 became an option on the Rainier. Worst case scenario you would then not have a G80 but on non-off road situations the electronic traction control will perform a similiar function as the G80. I'm on my third 360.
 

The_Roadie

Lifetime VIP Donor
Member
Nov 19, 2011
9,957
Portland, OR
DenaliHD66 said:
Edit: The only thing I don't get, is I thought if they were both open diffs, there wouldn't be any turning friction on pavement at low speeds? Why do I still get the crow hopping then? I understand the front axle is taking a different path than the rear, but even if they are connected, shouldn't they be turning freely? Is it any worse/better with limited slip differentials?
I was curious about this years ago, and figured it out. The front and rear can both be open, but that just means when all four tires have traction that the differential AVERAGES the driver's side RPM and the passenger's side RPM and its driveshaft to that diff spins at the average of the two side's speed. But since the front turning radius is different then the rear because the turning point is in line with the rear axle and thus farther from the front axle, that the rear and front driveshafts attempt to spin at different speeds. But the transfer case is locked up in the middle and tries to keep them spinning at the same speed. So you get driveline binding.

AWD vehicles usually have a viscous clutch and allow more slippage in the transfer case, so they don't bind up.

View attachment 17184
 

Attachments

  • envoyturning.jpg
    envoyturning.jpg
    76.2 KB · Views: 225

fishsticks

Member
Nov 21, 2011
433
HARDTRAILZ said:
Do you run the same in front? What do think is best with the lockers, brand, additives, whatever?

I run Royal Purple 75w140. The instructions say you can run 90 weight just fine, but the 140W is shock proof. Also, it seems to keep the lockers really quiet. I have ZERO of the telltale clicking you get from LRs when turning, even with my front always engaged. You wouldn't know they were there. You could run Redline or M1 too... I don't think brand is a really big issue, RP is just on the shelves here.


DenaliHD66 said:
Good stuff guys. No wonder I had such a bad experience under the impression I was running with LSDs haha. Well that NoSlip locker sounds legit then, and I'm interested to hear what works for the front end as well? Is the one you posted from ebay cheaper than Eaton's but just as good? Also do I have the same front diff size as all other GMT 360s, and if so what is it?

Edit: The only thing I don't get, is I thought if they were both open diffs, there wouldn't be any turning friction on pavement at low speeds? Why do I still get the crow hopping then? I understand the front axle is taking a different path than the rear, but even if they are connected, shouldn't they be turning freely? Is it any worse/better with limited slip differentials?

You will crow hop on pavement because there is still binding in the drivetrain even with open diffs. If you lock the front as well you won't be using 4WD on pavement ever again, the truck becomes a monster to turn. It's amazing for off road obstacles though.
 

DenaliHD66

Original poster
Member
Dec 4, 2011
597
fishsticks said:
I run Royal Purple 75w140. The instructions say you can run 90 weight just fine, but the 140W is shock proof. Also, it seems to keep the lockers really quiet. I have ZERO of the telltale clicking you get from LRs when turning, even with my front always engaged. You wouldn't know they were there. You could run Redline or M1 too... I don't think brand is a really big issue, RP is just on the shelves here.




You will crow hop on pavement because there is still binding in the drivetrain even with open diffs. If you lock the front as well you won't be using 4WD on pavement ever again, the truck becomes a monster to turn. It's amazing for off road obstacles though.

So what differential do you have up front then, a locker or one that transmits power from one side to the other? Like a Torsen differential?

Does limited slip show worse symptoms on turning on pavement in 4WD than open diffs, because of the differential clutches? I guess it would be the same, since all 4 wheels are rolling freely and no traction is being compromised. I'm just really taken aback, I thought I knew a good bit about this stuff by now, and I find out I don't even have LSD. That does explain the poor off-road performance though and getting stuck on a few occasions.
 

Sparky

Member
Dec 4, 2011
12,927
A properly working LSD on dry pavement in a turn should behave similar to an open diff in general, with a few exceptions. Depending on the design of the LSD, if you apply enough power around the turn it may apply enough torque on both sides to spin the inboard wheel to keep it up with the outboard - but if you're applying enough power to do that, it can also just break both free and send the back end kicking out on you. Ask me how I know :lipsrsealed:

The open diff will always be the most tame around turns, spools the hardest around turns, with limited slip and locker units in the middle (where in the middle depends on the particular unit).
 

fishsticks

Member
Nov 21, 2011
433
DenaliHD66 said:
So what differential do you have up front then, a locker or one that transmits power from one side to the other? Like a Torsen differential?

Does limited slip show worse symptoms on turning on pavement in 4WD than open diffs, because of the differential clutches? I guess it would be the same, since all 4 wheels are rolling freely and no traction is being compromised. I'm just really taken aback, I thought I knew a good bit about this stuff by now, and I find out I don't even have LSD. That does explain the poor off-road performance though and getting stuck on a few occasions.


Like Sparky said, open diffs are the easiest to turn.


I run a LR in the front. In 2WD the front driveshaft is dead, so it's like the LR isn't even there. The "problem" comes when you put it in 4WD. Off road it's not bad to turn the front wheels as the tires will slip a bit. On pavement they grab and you'll be fighting the wheel and probably hurting some steering components. I definitely wouldn't want to be in an emergency turning situation on pavement in 4WD.
 

DenaliHD66

Original poster
Member
Dec 4, 2011
597
fishsticks said:
Like Sparky said, open diffs are the easiest to turn.


I run a LR in the front. In 2WD the front driveshaft is dead, so it's like the LR isn't even there. The "problem" comes when you put it in 4WD. Off road it's not bad to turn the front wheels as the tires will slip a bit. On pavement they grab and you'll be fighting the wheel and probably hurting some steering components. I definitely wouldn't want to be in an emergency turning situation on pavement in 4WD.

Are there any options for a mechanical locker for the front then, that only engages when slipping?
 

fishsticks

Member
Nov 21, 2011
433
DenaliHD66 said:
Are there any options for a mechanical locker for the front then, that only engages when slipping?


The LR is the ONLY traction option for our fronts. The only reason it exists is because we share the same carrier as the S10s.
 

DenaliHD66

Original poster
Member
Dec 4, 2011
597
fishsticks said:
The LR is the ONLY traction option for our fronts. The only reason it exists is because we share the same carrier as the S10s.

Got a link for one? I'll bookmark it and let time decide if I should get one or not :tongue:
 

ScarabEpic22

Member
Nov 20, 2011
728
DenaliHD66 said:
Got a link for one? I'll bookmark it and let time decide if I should get one or not :tongue:

If you dont plan on wheeling regularly, dont put a locker/lsd up front. You will hate it unless its a trail rig. Put a LSD/locker in the rear for a DD and leave it alone.
 

djthumper

Administrator
Nov 20, 2011
14,956
North Las Vegas
ScarabEpic22 said:
If you don't plan on wheeling regularly, don't put a locker/lsd up front. You will hate it unless its a trail rig. Put a LSD/locker in the rear for a DD and leave it alone.

:iagree:
 

DenaliHD66

Original poster
Member
Dec 4, 2011
597
Yeah like I said, definitely not something I'd consider unless I DO turn it into an off-road rig. *Bookmarked*
 

HARDTRAILZ

Moderator
Nov 18, 2011
49,665
ScarabEpic22 said:
If you dont plan on wheeling regularly, dont put a locker/lsd up front. You will hate it unless its a trail rig. Put a LSD/locker in the rear for a DD and leave it alone.

Remember that a LSD is not really good for any offroad. Sending the power to the tire with less traction is not going to help much.
 

navigator

Member
Dec 3, 2011
504
my understanding with a front locker is when you aren't in 4WD, you don't know it is there at all. It wouldn't seem to affect a DD as much as a rear locker in that case.

If I do a locker it will likely be in the rear because of my use and it would be much easier.
 

HARDTRAILZ

Moderator
Nov 18, 2011
49,665
I figure if I lock one up right, I ought to lock the other and really have 4x4.
 

ScarabEpic22

Member
Nov 20, 2011
728
HARDTRAILZ said:
Remember that a LSD is not really good for any offroad. Sending the power to the tire with less traction is not going to help much.

Good point, guess most guys over here are looking for a more offroad setup than a street one. I wouldnt put a locker in my SS ha!

navigator said:
my understanding with a front locker is when you aren't in 4WD, you don't know it is there at all. It wouldn't seem to affect a DD as much as a rear locker in that case.

If I do a locker it will likely be in the rear because of my use and it would be much easier.

Hmmm I guess so, Im just worried the front diff might not like it if the xfer case randomly engages while driving around town...

But it definitely wouldnt affect a DD as much.

HARDTRAILZ said:
I figure if I lock one up right, I ought to lock the other and really have 4x4.

I've debated doing this with my SS, that way I get 4 wheels moving not 3. But I doubt the front diff can hold the power, especially with my future plans for it (427+blower).
 

The_Roadie

Lifetime VIP Donor
Member
Nov 19, 2011
9,957
Portland, OR
ScarabEpic22 said:
... But I doubt the front diff can hold the power, ...
There are multiple elements of our drivetrain, all clamoring to be crowned the WEAKEST PART. :rotfl:

CV joints. CV shaft splined ends. Splined disconnect collar and fork. 7.25" ring gear front diff. 8.0" ring gear rear diff. Ujoints. 28-spline rear axles.

Inner and outer tie rod ends and anti-sway bar end links are competing in the separate suspension element welterweight division.

About the only thing not underengineered is the transfer case chain and the Panhard bar. But an internal bearing support WAS to the point New Venture Gear had to redesign it around 2005. Definitely a love/hate relationship with this platform.
 

DenaliHD66

Original poster
Member
Dec 4, 2011
597
What's "DD" that you guys have been saying?

@ the guy who wanted to lock the front end on the TB SS. I definitely WOULD NOT because you aren't going off road, and its AWD so its always engaged. You wouldn't be able to turn anywhere :tongue:

I definitely want the rear one, and it seems affordable enough, at least to have someone install it for me and fill it up properly. I'll think long and hard about the front, I guess it depends if I keep my truck that long, and decide to add a lift kit to it and all that, otherwise not worth it. XL ground clearance isn't the best :tongue:
 

navigator

Member
Dec 3, 2011
504
DD means daily driver, you drive it on the highway and not exclusively a trail rig.
As far as the front locker, I didn't think about AWD, I guess that could potentially cause problems but don't really know.
 

fishsticks

Member
Nov 21, 2011
433
the roadie said:
There are multiple elements of our drivetrain, all clamoring to be crowned the WEAKEST PART. :rotfl:

CV joints. CV shaft splined ends. Splined disconnect collar and fork. 7.25" ring gear front diff. 8.0" ring gear rear diff. Ujoints. 28-spline rear axles.

Inner and outer tie rod ends and anti-sway bar end links are competing in the separate suspension element welterweight division.

About the only thing not underengineered is the transfer case chain and the Panhard bar. But an internal bearing support WAS to the point New Venture Gear had to redesign it around 2005. Definitely a love/hate relationship with this platform.


I have already broken more than half the parts on that list you gave. :biggrin:
 

ScarabEpic22

Member
Nov 20, 2011
728
Ideally a locker that isnt always engaged would be best for the front, unfortunately as Donny, Bill, and others have said we're screwed on options. It would be a bad idea for the SS unless it was a drag car to get the power to the ground all the time, but its my SS so not going to happen.
 

DenaliHD66

Original poster
Member
Dec 4, 2011
597
fishsticks said:
I have already broken more than half the parts on that list you gave. :biggrin:

Going to get suspensionmaxx links next time around. Hotchkiss sway bar and front poly bushings have all sides clunking with body twist or roll.
 

fishsticks

Member
Nov 21, 2011
433
DenaliHD66 said:
Going to get suspensionmaxx links next time around. Hotchkiss sway bar and front poly bushings have all sides clunking with body twist or roll.


Wait and get Mike's new quick disco links once he's done testing them. Cheaper and better.
 

ScarabEpic22

Member
Nov 20, 2011
728
fishsticks said:
Wait and get Mike's new quick disco links once he's done testing them. Cheaper and better.

:iagree: Smaxx links have had some problems in the past, cant talk about them now but Id wait for Mike's links. Saw pics of them, they look sweet.
 

DenaliHD66

Original poster
Member
Dec 4, 2011
597
Interesting. Well as far as I'm aware, here's how the line of succession goes:

OEM Sway bar links < Moog < SuspensionMaxx < and now Mike's?
 

ScarabEpic22

Member
Nov 20, 2011
728
Eh Id probably say the Moog links are overall worse than the OEM replacements. Im on my 3rd set of endlinks on the 02, OE, then Moog, and now Oreilly replacements (cant remember the brand offhand). I kept the Moogs greased every 5k, and they were still clunking badly after only ~25-30k. I left them on for 50-55k because I didnt want to mess with them and dealt with the noise. Have about 20k on the Oreilly replacements, retightened them once after ~1k (did it with the Moogs too) and they're still nice and quiet.
 

DenaliHD66

Original poster
Member
Dec 4, 2011
597
I got the Moogs put on my rear because they were greasable and thought they'd hold up better than OEM. My front OEM ones are the ones clunking around big time, the rear only does it on occasion. But like you said, I'll deal with the noise until they are actually shot then get something better.
 

DenaliHD66

Original poster
Member
Dec 4, 2011
597
Off topic but is there a thread that is covering these new sway bar links that someone is coming out with?
 

Forum Statistics

Threads
23,676
Posts
641,857
Members
19,113
Latest member
SCr

Members Online