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2011 rear axle codes and questions

Bailey mays

By Bailey mays
in Ask A GM Technician

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Bailey mays Enthusiast

Bailey mays

Posted
Posted

I have a 2011 z71 and I have codes g80 and gu6 which im sure is automatic rear locker and 3:42 gear ratios my question is with the automatic locking rear how does it work in unison with spider gears or do I even have spider gears? I have had a shop tell me I need spider gears replaced but with the locker im not sure how this works if anyone can clarify I would greatly appreixate it Thankyou

newdude Senior Enthusiast

newdude

Posted
Posted

 

 

Videos work best for describing it.

 

As far as I know all diffs have spider gears as they are what allow you to turn corners. Make a left, the inside wheel spins less revolutions than the outside wheel. Opposite for right turns. If they were stuck/welded, you would chatter and hop every turn you make.

Jsdirt Senior Enthusiast

Jsdirt

Posted
Posted

Yep - gotta have spiders ... or the diff no worky.

Jsdirt Senior Enthusiast

Jsdirt

Posted
Posted

:D:cheers:

Doug_Scott Senior Enthusiast

Doug_Scott

Posted
Posted

What is your truck doing that a shop is suggesting replacement of the side gears? Are you trying to correct a noise, or rattle type effect of the differential when one wheel starts to slip?

 

"Spider gears" is one of those terms that I just don't get. They don't have 8 teeth on them, they have nothing in common with a spider, or even any of the things a spider does. I remember back in high school that answering a differential question, using the term "spider gears" was marked wrong, differential side gears were marked correct.

 

Don't ask me about cob webs either.....

Jsdirt Senior Enthusiast

Jsdirt

Posted
Posted

That could be another one of those old New England terms that spread. If you spin both wheels in opposite directions with the cover off, the side gears kind of resemble the way a spider scurries around, out of the corner of your eye. Guess you have to have a big imagination .. :lol:

 

 

 

Now this is a pretty accurate description of a spider these days - see the resemblence? :D

 

post-65085-0-48650800-1427030092_thumb.jpg

 

post-65085-0-14016000-1427030170_thumb.jpg

post-65085-0-48650800-1427030092_thumb.jpg

post-65085-0-14016000-1427030170_thumb.jpg

post-65085-0-48650800-1427030092_thumb.jpg

post-65085-0-14016000-1427030170_thumb.jpg

post-65085-0-48650800-1427030092_thumb.jpg

post-65085-0-14016000-1427030170_thumb.jpg

gmtech4 Senior Enthusiast

gmtech4

Posted
Posted

Thx JS now I'm arachnophobic !!!!!!! ( I hope I got the right word ) lol

 

I'm with doug on this, dumb name , side gears actually tells of their location as well lol

Bailey mays Enthusiast

Bailey mays

Posted
  • Author
Posted

Thanks guys I was almost positive spider gears had to be there but I had a friend who was arguing with me for close to an hour saying that I didn't even have spider gears for one and did not even have the locking rear differential. He was saying that with an automatic locker you don't have spider gears that the locker replaces that but he drives a jeep so his intelligence level we can already tell is low lol just kidding hopefully I don't offend anyone Thankyou guys for the replies

Doug_Scott Senior Enthusiast

Doug_Scott

Posted
Posted

Detroit lockers, and True-Trac lockers do not have traditional side gears, and most definitely do not have any gear resembling the shape of what some call spider gears. There are a few differentials that do not use the typical 4 gear setup that just about all open differentials use.

 

Detroit lockers operate in reverse of just about all other locker type differentials, they start off locked up, and will 'ratchet' on corners. Take a look at how the True-Trac works if you want to see pure simple physics.

 

It always amazes me that some guy can be just sitting eating corn flakes one morning and while he tries to swat a fly he comes up with a way to lock up a differential. Best I ever managed at breakfast was to fart and not bite my tongue due to the distraction.

gmtech4 Senior Enthusiast

gmtech4

Posted
Posted

Detroit lockers, and True-Trac lockers do not have traditional side gears, and most definitely do not have any gear resembling the shape of what some call spider gears. There are a few differentials that do not use the typical 4 gear setup that just about all open differentials use.

 

Detroit lockers operate in reverse of just about all other locker type differentials, they start off locked up, and will 'ratchet' on corners. Take a look at how the True-Trac works if you want to see pure simple physics.

 

It always amazes me that some guy can be just sitting eating corn flakes one morning and while he tries to swat a fly he comes up with a way to lock up a differential. Best I ever managed at breakfast was to fart and not bite my tongue due to the distraction.

Hilarious ..... Now can you change that icon you have so I don't have nightmares about little bugs walking around my computer screen ???? Thx lol

Jsdirt Senior Enthusiast

Jsdirt

Posted
Posted

LOL!

 

Oh yeah forgot about those Detroits. Where I come from, nobody could afford them, so I never got to see one in person. :D Always wanted one for my '72 El Camino.

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