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2015 Silverado 1500 Z71....Open rear?????

GsBowtie

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GsBowtie Enthusiast

GsBowtie

Posted
Posted

Question for you all..

 

I had my Silverado out in my yard last night loading fire wood, my wood pile is on a slight downward grade and when I went to pull out, the right wheel spun, the left did not. This happened twice last night. It also happened one time before going over a steep curved curb at my brother in law's house (spun).

 

I thought these trucks, and the Z71 had posi rear diffs? Why is one spinning and the other not if this is the case (I dont know which one spun last time, but it did spin).

 

Any thoughts or comments would be appreciated. Is this normal? I know it's not a locking rear, so I know it CAN happen even on a posi rear, but I was suprised to have these traction problems.

 

Thanks,

Greg

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Clocked92 Enthusiast

Clocked92

Posted
Posted

I have a Sierra All Terrain which includes the Z71 package. I believe these trucks have a G80 locker which will engage the other drive wheel if it senses the main drive wheel slipping. Someone please correct me if this is wrong.

 

Just the other day I was backing my trailer onto my driveway and I had to give my truck a little gas to get the back tires over the steep rolled curb. After I unhooked and parked, I noticed there were 2 tire marks where the tire spun on the curb.

MikeNH Senior Enthusiast

MikeNH

Posted
Posted

GM trucks haven't had the traditional posi diffs in ages. They have a locking differential as an option (G80). It can be fussy about locking up. Both of mine were.

 

Check the RPO sicker in you're glovebox for G80. It should be there.

newdude Senior Enthusiast

newdude

Posted
Posted

Question for you all..

 

I had my Silverado out in my yard last night loading fire wood, my wood pile is on a slight downward grade and when I went to pull out, the right wheel spun, the left did not. This happened twice last night. It also happened one time before going over a steep curved curb at my brother in law's house (spun).

 

I thought these trucks, and the Z71 had posi rear diffs? Why is one spinning and the other not if this is the case (I dont know which one spun last time, but it did spin).

 

Any thoughts or comments would be appreciated. Is this normal? I know it's not a locking rear, so I know it CAN happen even on a posi rear, but I was suprised to have these traction problems.

 

Thanks,

Greg

 

 

X3 not a posi. Its the Eaton G80 locking differential. Watch this to see operation:

 

Mechanical lock with some limited slip action via the clutches. Otherwise its an open diff with mechanical lock.

robvas Enthusiast

robvas

Posted
Posted

the one tire probably spun for a second then the locker grabbed on then both tires gripped and got you out

MikeNH Senior Enthusiast

MikeNH

Posted
Posted

My non-Z71 lays down two nice, even strips of rubber.

G80 isn't specific to Z71s and open diffs can light up both tires in the right conditions. Back in high school a kid I knew did a reverse burnout, up hill in a manual transmission Civic. Both tires left stripes.

GsBowtie Enthusiast

GsBowtie

Posted
  • Author
Posted

Thanks guys. Ok so no posi then it supposedly has the locker but it's not locking up then. For sure it didn't spin both and it didn't lock up. .. [if it ever did] until i baked off and tried again. I almost had to use 4x4 which is crazy

TxTruckMan Senior Enthusiast

TxTruckMan

Posted
Posted

I'd take it to the dealer. I've never had a problem getting my rear to lock up on any GM vehicle with a locker.

SouthernSilveradoGuy85 Senior Enthusiast

SouthernSilveradoGuy85

Posted
Posted

I had the G80 in my 98 and also in my current truck, a '14. The G80 both helped me out a lot while also sometimes either wouldn't lock in posi when I needed it to and also would lock in posi when I didn't need it to. In general the G80 is great when it works but you can't assume it will kick in. So it's not 100% reliable. I haven't gotten into a situation in my '14 yet where I needed or hoped the G80 would kick in posi so I can't say rather it's more reliable than the previous years. So just because it didn't lock in posi when you needed it doesn't mean there's a problem, it's just how it is for the most part. From what I can remember, it seems harder for it to lock in posi when backing up. Backing up and then going forward on the other hand seems to lock it in everytime.

larryz71 Enthusiast

larryz71

Posted
Posted

Noob question.. Does turning off traction control effect whether or not the G80 locks?

 

 

Sent from my iPhone using Tapatalk

larryz71 Enthusiast

larryz71

Posted
Posted

What is the purpose of turning off traction control then?

 

Not to high jack the thread just thought it may be relevant to your question OP

 

 

Sent from my iPhone using Tapatalk

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