Jump to content

Recommended Posts

Posted

I have an open end rear differential. I was wondering if I could switch out some gears so I could have a locking rear end, or would I have to get a whole new rear end? I have a 2001 GMC Sierra 1500 SLT 2x4 5.3 Extended cab, if that helps for you specificity oriented people.

Posted

Many options, but you need to decide if you want a locker (gear to gear, positive lockup) or a limited slip (uses clutches to limit wheel slip).

 

I will only recommend shying away from so called lunch-box lockers that replace the side gears. They are cheaper, easy to install, but can create issues later on.

 

Sent from my SAMSUNG-SM-G900A using Tapatalk

Posted

You can replace the open differential with a number of different types; limited slip, locking, torsen and a few others.

 

The stock one for your truck would have been the G80, which is the stupidest design ever engineered. It's literally designed to be a time bomb. It is a locking type, but will only do so under certain circumstances, and often won't when you need it to. Or, will lock up when you don't want it to.

 

For normal use, I also recommend the Truetrac, which is a Torsen type. It isn't a locker, such as Nitro Dasik noted, but uses a clever design to transfer power to the wheel with the most traction. A locking type literally locks the 2 rear axles together.

I bought my Truetrac at Summit, as it had the best price at that time. I strongly recommend you have someone install it that knows what they're doing.

Posted

I have to disagree - look up g80 on you tube and you will see how it outperforms lsd on other manufacturers trucks, and only implodes when abused - and no more than any other stock set up. I do agree with the truetrac for replacement. I replaced my open diff a few years back on my 2011 avalanche with a truetrac, and it is a great improvement. I also did my gears from 3.08 to 3.42 at same time, and 4wparts will sell and install. Remember you need to change fluid 500-1000 miles after you switch (which is diy), but let a pro do the install. I loved how it worked on my 2wd (worked great on boat ramp), and would not have upgraded to a 4wd but they discontinued the model, and I wanted a loaded final edition...

 

Sent from my SM-T350 using Tapatalk

Posted

I have to disagree also the G80, its a good locker as I have had them since 1987 in several trucks and not one has blown up, I have 4 wheeled alot and had it in ruff conditions but if people do burn outs, doughnuts spinning the rear wheels like a mad man in mud and so on (abuse it) sure your going to blow it just like any other locker. Hell I use to run 42" Swampers with the G80 and never had a problem. A lot of people who blow them just don't know how to use a locker.

Posted

X3 on disagreeing that the G80 is junk. I have put at least 2,000,000 miles on G80's since the early 1980's. Never had one fail, although I have had my fair share of rear differential failures from pinion bearings failing and axle seals and bearings. Most miles on one truck was just shy of 500,000 and I have a truck in the driveway that has about 308,000 miles on that G80. It had a complete rear differential installed at about 4000 miles after I had 3 failures (not G80 related) in the first couple of months of ownership.

Posted

You guys can disagree all you want, but IMO the G80 is an inherently stupid design for use in the real world. It's idiotic to design something that crashes small parts together under high shock loads in order for it to work. They don't just go bang from abuse, they often explode for no reason at all. They can also lock up when you don't want them to. Or, just not work at all when you need them.

I'm not the only one with this experience.Various forums are littered with complaints about them.

 

Also, the G80's of today aren't the same as the ones in the 80's. The G80's in the 80's were limited slip positraction units with clutches. I'm not sure when GM started spec'ing the Eaton crash and smash locking units under the G80 code.

 

The one I pulled out of my 06 was troublesome almost from new. I certainly didn't abuse it. It worked mostly ok for the first 30-40,000km, but then would sometimes leave me hanging in the winter. I took it to the dealer under warranty and it worked fine for another 20-30,000km. Then it started locking up when it felt like it. Not fun on dry pavement. After trying a bunch of things and futzing with it for a long time afterwards, I finally pulled it out and threw it away. Replaced it with a Truetrac. I'm just glad that G80 never grenaded on me.

 

 

At least we agree that the Truetrac is a good unit. It's also a lot cheaper to buy than a G80.

Posted

 

 

:thumbs:

 

 

 

 

At least we agree that the Truetrac is a good unit. It's also a lot cheaper to buy than a G80.

:cheers:

  • 1 month later...
Posted

The g80 syntrifical has clutches with a slide bell between the spider gears they only work correctly if the left rear tire spins first but how ever if your foot isn't off the throttle before it locks it does look like a time bomb went off in the diff case if I could figure out how to post pics I would show you what I mean do not recommend the g80 which is a limited slip locker combo they are junk

post-170776-0-04644600-1490064456_thumb.jpg

post-170776-0-04644600-1490064456_thumb.jpg

post-170776-0-04644600-1490064456_thumb.jpg

post-170776-0-04644600-1490064456_thumb.jpg

Archived

This topic is now archived and is closed to further replies.

  • Latest Articles

  • Posts

    • "Teardown" is complete. Head surfaces are clean and ready, new intake is prepped and ready. Coolant drained and water pump is removed, radiator is removed, new hoses and pump are ready.   The replacement intake is also from a '95 (with I think 260k, the odometer said). Noticeably less pitting where it covers the rear coolant passages. I'm not sure if that's a tribute to more frequent use, more frequent coolant changes/upkeep, or if the intake was machined at some point. But it appears I found a good one.   My coolant hoses were original, and the lower hose still retained the factory spring inside. It's not really rusty, but it's got deposits all over it. Unsure if I should re-install it (will thoroughly clean it first). Someone said hose technology has gotten better since 1995 (has it?) and I don't need the spring. I think modern EPDM is what made those hoses last from 1995-2026, so it's a question of how much suction can the water pump really pull, and will it collapse the hose without a spring?   I'm stopped and waiting for parts, however.   When I first brought the truck home, the fan was intermittently hitting the radiator shroud. I could see someone had monkeyed with the shroud (put a bunch of cardboard as a spacer between the upper/lower shroud halves. Someone said the motor mounts have likely failed and the engine has sagged. I wasn't sure I believed that. The engine is really solid in its mounts: To remove the old intake I *just* nearly permanently welded to the heads with freshly cured RTV and gasket snot two weeks ago, I literally had to use the arms on my lift and a chain with a bolt attached to the intake to pull it loose. It almost picked the front of the truck off the ground before ....scuuuuuuuuuuup.... I could actually hear the gaskets tearing and it broke loose and the whole truck settled back down. Motor barely moved.   SO, those parts I'm waiting on... The lower radiator mounts/bushings had completely failed. The radiator needs to be insulated from the rad support, and the bushings help the rad stand at the correct height. The plastic "baffle" was also destroyed at some point. Someone had attached the shroud to it incorrectly, overlapping a joint that should have been underlapped, creating another suspect issue potentially causing things to hit the fan. Broken tabs, side is busted off, and it's perma-formed/bent where it was jimmied incorrectly.   The baffle? Unobtainum. Long since discontinued from GM, of course. Aftermarket/capa/chinese? Also unobtanium. In GM's infinite wisdom, it appears there are at least two different variations whether the Blazer is 2 or 4 door, and I can't yet tell if they shared the same part with the S-pickups. Plan B, if I can't find a viable used one, will be to create a bracket to re-assemble the critical joint I need to seal a gap with the shroud. But that will bug me, it won't be...perfect.   The water pump bolts appear to have been installed with...plumber's putty. I guess, sure, if it works...? I've found a few "backyard fixes" like that. Someone's been here before....   If I can't find someone to jam bamboo under my fingernails to fill my free time this week I think I'll install the driver's power window motor and replace the rear door speaker that's inop. I've got a genuine GM "9.5" ohm working replacement. Why GM used a non-standard resistance....nevermind. Of course they did, you can get more sound from a cheap factory amp that way.   And the saga goes on...
    • // Thank you, also for your  response. More information is always good. This 2013 GMC is most likely my 'forever truck"-I'm 77 and retired...and truck only has 42K on it-very clean-so I try to keep it that way.  Tks again for your  response- glenn
    • I started my install this weekend. Everything was pretty straight forward but I ran into one issue with running power through the firewall. The nipple grommet on my High Country already has a small harness running through it - has anyone else ran into this issue? And on the engine bay side, does the wire basically just penetrate the factory wiring boot? I did this on my '22 Trail Boss and it seems much easier but thats been a few years. My other thought would be possibly drilling a new hole adding a rubber grommet just to the lower left of the factory hole. Thoughts?   Has anyone used a T-harness off the Bose amp and obtained power from there? It seems a little odd that such a small amp needs 3 power leads
    • ///// Ok--Thanks for that info--I could not find yesterday when I looked for the specs on that NAPA filter what I wanted. Their website is not very user friendly. I buy all teh filters for  our three vehicles once or twice a year. Have always run NAPA Gold on everything I own....I buy it thru my Son's account for his business-which he has a Heavy Equipment repair shop-one reason he uses NAPA so much-they have such a full line of coverage for just about anything/anywhere- He gets s  good discount because of volume bought. Anyway-Thank you -Sir for your response.   glenn
    • It is possible to add your own 12v outlet to your truck.  Check out this video:   I verified via GM Upfitters that pin 31 is the same on the 1500 trucks.  The wire is GM part number 84779405.   You can get the GM 12v outlet from Amazon  https://www.amazon.com/Genuine-Accessory-Receptacle-25774623-13549530/dp/B0F1H9YRGF EWAY 12 Volt Power Adapter for GM   https://www.amazon.com/EWAY-Chevrolet-Silverado-Cigarette-Ignition/dp/B0915RRW6Q/ref=sr_1_1?   I just haven't figured out a good place to put the 12v outlet in my truck.   Some people are getting USB-C to 12V adapters  https://www.amazon.com/WYMECT-Cigarette-Lighter-Socket-Adapter/dp/B0F87WNQKB/ref=sr_1_1_sspa? Not sure if they provide the correct amperage that a device like a tire inflator would need.  
  • GM-Trucks.com Clubs

  • Popular Contributors

×
×
  • Create New...