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Locking rear end?

Discussion in 'Chevy Trucks' started by NYRookie, Nov 10, 2003.

  1. NYRookie

    NYRookie Member
    Messages: 41

    I currently own a 2002 GMC 2500HD with a regular 4:10 rear. I was wondering if a locking rear would make that much difference. I wanted one when I bought the truck new, but they couldn't find 1. What are the pro's and con's? Any comments welcome.
     
  2. Radguy

    Radguy Member
    Messages: 72

    A locker makes a big difference. The only major draw back is little more wear on the tires. And the ratcheting sound they make. The top end ones like detrioit locker is quieter than lock-right and the other cheaper brands.

    If you wanted to invest some money you can buy and ARB locker. That way all you can lock it if you want and unlock it when it's not needed.

    Or you could just weld the Spider gear and have a lincoln locker:D
     
  3. Perkin50

    Perkin50 Junior Member
    Messages: 5

    The locker you are referring to is the Eaton Mechanical locking differential. It has been sold as the G-80 option in GM trucks for years. Recently it is is standard on the Z-71 and ZR-2 package. It works like a convential open differential during normal driving. But when one tire spins and there is a 20rpm difference between left and right wheel speed the unit will lock. And when the throttle is released you will have to do an S turn and the unit will automatically unlock.This is extremely useful in almost any circumstance when you begin to have one wheel spinning. It is automatic and only engages when it is needed. I have this unit in my truck and works perfect for the kind of driving I do and I have never got stuck with this unit.. Eaton also has a Electronic locking differential which is similar to the ARB air locker except it uses electrical power so there is no need for a bulky compressor and lines like the ARB unit. This unit locks the differential from a switch. It is standard in the new Hummer H2. The only draw back is that it must be engaged when the vehicle is stopped. And then when you want to disengage the unit the vehicle must be stopped again. This is perfect for the offroader who locks the unit before goining off-road and then when they are done they stop and unlock the unit. But not as ideal as the M-locker for the everyday driver. There is detailed information at Eatons site on these units. WWW.torquecontrol.eaton.com
     
  4. ratlover

    ratlover PlowSite.com Addict
    from IL
    Messages: 1,325

    Perkin 50 is right on except I find the factory locker(gov lock) fairly easy to overpower(still get the 1 wheel wonder). I also dont think the drive in a S to unlock it. The thing was designed so soccermoms and the rest of the driving public wouldnt notice it being there most times and wouldnt get themselves killed. Its a compromise locker. It will help out in the snow a bit though. A real locker would give better traction but you might have to learn how to drive with it as they can be a bit quirky. You will notice no difference in tire wear with any type of traction aid(clutch type posi, real locker, or a gov lock) if you dont drive like a maniac. You also wont notice any ratchiting with a gov lock and you can learn how to drive a real locker so it isnt noticable.

    Me personally.> For plowing I would try to get ahold of a factory unit that somone yanked in favor of a real locker. If I couldnt find one used for cheap I would get a detroit. If I was going to have different people driving it(wife, kid, goober employee) I would not put a detroit in it for fear of them wrecking my truck. I would leave it open or go with a gov lock. I would not use a clutch type limited slip.

    A good driver can go through alot of snow gov lock or not. You will probably be fine with an open diff. The cost of puting a traction aid in there will be pretty steep especially if you pay install.

    And I also dont think a locker is standard on a z 71......but things might have changed on the brand new trucks........
     
    Last edited: Nov 12, 2003
  5. calhoun

    calhoun Senior Member
    Messages: 165

    Locker adds an extra drive wheel. The G80 unit is fine for normal usage. Perkin50 discribed it well. He left off one "feature". It will not lock and will unlock at speeds greater than 20mph. (If you are going that fast you are not stuck). This is so average drivers can maintain control. In this sense it is a compromise locker, but when it is locked it is locked. I cannot overpower mine (untill speed gets over 20 than it disingages.) I have pulled against a wall, jacked one tire off the ground and the tire still on the pavement will spin.
     
  6. ratlover

    ratlover PlowSite.com Addict
    from IL
    Messages: 1,325

    I have been at a stop and mashed the go pedal and had a one wheel light up. I've had it happen on different trucks, dry and wet pavement.

    A gov lock does do its intended purpose well, as a compromise. I just dont personally like how it works. Its not predictable IMO, sometimes it locks and sometimes not. I have had it acting like it was enguaged at higher speeds......most times when I light up the tires in an open diffed vehical the one wheel does nothing and it acts like a rudder......I have had gov lock equiped vehicals nuking both tires.....I dont know.....maybe there was 100% equal traction to both tires(or lack of) I dont know and a open diff would have broke em both lose. Its kinda entertaining to light up the tires from a 45 MPH roll :dizzy: I was thinking of trying it from a higher speed but didnt have the cahones :rolleyes: I have also experinced the same thing in the snow at higher speeds.

    Gov locks are plenty beefy IMO in the bigger axels but I wouldnt run one in a 10 bolt. JMO

    If you are stuck at slow speeds you can ussually ride the brake and send power to the other tire. Spinning fast in snow/ice is a great way to break stuff BTW so dont do that.
     
  7. Radguy

    Radguy Member
    Messages: 72

    No difference in wear? Hmmmm my friend had a Dodge Dakota with a detriot locker. The only way it wouldn't chirp the inside tire was on a wide turn. That's pretty hard to do in the city. If you live in the country then maybe no wear but if you have to make any sharp turns on pavement, you will wear your tires more. The ratcheding just can't keep up.

    And the thing that's most likely to break as far as horseing it would be a universal, then possibly an axle, don't really think you'll break an axle on your HD2500 though.

    Unless you do like Calhoun does with the jacking and spinning the other tire, on pavement.
     
  8. ratlover

    ratlover PlowSite.com Addict
    from IL
    Messages: 1,325

    Shorter the wheelbase the more noticable a detroit is. If you are on the gas going around a corner it will send power the the wheel spinning the slowest. Its the way a detroit is designed. It will only allow one tire to spin faster than the other one, it will not allow a tire to spin slower. Sounds the same but there is a very big difference. The ratcheting can keep up, the outside tire is the one that is spinning faster and allowing to "free spin", its trying to apply power to the inside tire. Have him stomp on gas, bet the inside tire breaks first. A clutch type limited slip will always send power to the wheel spinning the fastest with the clutchpack trying to keep the tires spinning together, its basicly like an open diff with help. A gov lock......well I know how they are supposed to work in theory ;)

    In tight turns like u turns its hard to not get em to ratchet/pop and sound like your eating gears and such but most of the time you can stay on the gas just right and get it to not be so noticable.
     
  9. calhoun

    calhoun Senior Member
    Messages: 165

    Just noticed NYRookie and Radguy are from upstate NY also. Just drove though your towns last weekend. I am from Mechanicville and was going up to my camp on Piesico Lake. Weather report says 6" tomarrrow for you I get 0.
     
  10. NYRookie

    NYRookie Member
    Messages: 41

    Calhoun, Radguy and I are just supposed to get snow squalls. Farther up north they are going to get 6". I go threw Piseco to go to our camp in Ohio. They had snow up there October 18.
     
  11. Perkin50

    Perkin50 Junior Member
    Messages: 5

    Thanks Calhoun.
    Yes your correct the unit has a reation block the at 20 mph carrier speed swings out to prevent engagement at 20 mph or higher.
     
  12. Perkin50

    Perkin50 Junior Member
    Messages: 5

    If you can overpower the M-locker in your truck is is probably worn out. You may also be running the wrong lube. The more torque you apply to the M-locker the more reaction force there is that forces the side gears into the housing and completely locks up. locked. With a good unit you will NEVER get one wheel peel.The M-locker is a very durable unit and very reliable and does great when plowing.This unit which is designed to run with the GM synthetic 75-90 will run 20,000 engagements on the test stand and have to overcome 850 lbs of torque. We have run these units they have no problems at 20k engagements. Most of the time they will unlock on their own but occasionally you need to do an S turn. As of 2003 with the Z71 and ZR2 package the M-locker is standard. Prior to 2003 the M-locker was an option. It was first introduced in 1972 in the 10.5 in the one ton, and is a two piece housing. As far as a ratcheting locker they suck in the snow. They will do good when plowing but driving around town or on the freeway you will be all over the road. That is why the E-locker is alot better than the ratchet style. They act like a conventional open when the are not engaged. But when your plowing you lock it up by pressing the switch and enjoy the traction. When your done plowing you unlock the unit by pressing the switch and then you have a safe open that you or your wife can safely drive around town with.
     
  13. ratlover

    ratlover PlowSite.com Addict
    from IL
    Messages: 1,325

    Have had a peg leg in my 03 2500hd with a few 100 miles on it before and after I changed the lube(factory grapejuice and then to mobild 1 75 90 synthetic) I've had it happen at stock power and well over stock power. Also had it happen in 1/2 tons with 10 bolts. It was real anoying to be at a stop and crank the wheel and munch the gas in my old z71 and drive around in a big circl slowly with smoke rolling off one tire. My 97 z 71 seemed to be the worse about not engauging/ acting like it was enguaged when I think it shoulda/not been. I guess I didnt really explain myself well......I dont *think* I ever overpowered it like it was enguaged and poped lose(if that were to happen I'm sure I woulda trashed it) it just isnt enguaging when it should(IMO and acording to what it is supposed to do). You can overpower a posi and get one tier to spin(they are ment to slip the clutches) but I'm *pretty sure* bad things would happen if you overpowered a locker of any sort.

    I missunderstood you about the unlocking. I can see how it might not unlock itself in some cases and needing to unload it to get it to go to normal, its finicky nature at work I guess. I thought you ment once it engauges you have to drive in a S to get it out.

    E-lockers or an OX locker would rule :nod: but the general driving public puts a kill on that. Really supprised the rubicorn gets em.

    I feel they are plenty beefy for the bigger axels but have seen them kerspload when IMO the shouldnt have in 10 bolts. JMO

    Like I have said.....the gov lock does what it was designed to do well, maniacs like me just wernt what it was designed for. :D

    I think we are on the same page just missunderstanding each other a bit :)
     
  14. Radguy

    Radguy Member
    Messages: 72

    So you know Rt 10 then!!!:waving:

    A few of my friends ride sportbikes and have been know to go to Piseco outlet and play on that mile long straight away. 2 years ago that bridge was sealed pretty good!!!

    Oh and about the locker...Just weld the spider gear and be done with it:nod: :waving:
     
  15. ratlover

    ratlover PlowSite.com Addict
    from IL
    Messages: 1,325

    Your joking right? :confused:
     
  16. Radguy

    Radguy Member
    Messages: 72

    Well in this case yes (only because you need something that's almost gauranteed to keep your truck running) but.......

    I've had it done on my suzuki samurai, had both diff. welded. Running 33" tires, this was only used for wheeling. But still the welds never broke!!! I've also seen it done with numerous wheeling vehicles with larger tires. I would only let someone that has years of experience welding, weld the gear though.

    Like I said, in this case I would never have it done. Only reccomend it to budget wheelers!!!:nod:
     
  17. ratlover

    ratlover PlowSite.com Addict
    from IL
    Messages: 1,325

    OK.....I do agree, "Lincoln" lockers have thier place. I just didnt think this was one of em.