anyone w/ gov-loc or locking diff

[benoit454]

Anyone who has or had a locking diff, or gov-loc setup....

ever had any problems with them thumping, or locking up or something? Like making a clunk feeling, no noise just feel, a thud, thump or click? Like someone was kicking the tire? Mainly on slow turns or from a stop and slow take off turn?

[James McClure]

Chris: First thing you want to do is pull the cover and look for metal. Detroit lockers were good for blowing the governor section to bits. If there is no metal, check the governor large gear, if that's ok, get a bottle of rear end additive from GM parts. Don't go with anything else OK? Fill rear part way and put additive into a fill bottle w\some fluid and finish fill. Take truck and do 1\2 dozen figure 8's nice and slow \easy and see what happens. Sticky clutches usually respond nicely to this, Jim

[benoit454]

well I've already pulled the cover and checked nothing is wrong inside, she's nice and clean. I bought some trans x posi trac additive and put in there and haven't drove it much yet. I wondered if anyone had done this and they added the additive and it worked.

It the all stock gov lock junk so I wasn't sure. If it had clutches I figured it be them sticking, but with the gov lock I don't think there' any clutches.

[LONGHAIR]

Detroit lockers were good for blowing the governor section to bits. If there is no metal, check the governor large gear,

Gov-lock and Detriot locker are not the same thing...not even close.
Gov-lock is a clutch type "posi" unit that "self adjusts". That little gear/governor mechanism is supposed to add pressure to the clutches. These are an "over-engineered" joke. The bigger 14-bolt units are supposed to be a fairly useable piece, but the lighter duty ones will not take much.

Detriot locker (No-Spin) has no clutches, it does not slip at all. It has large square teeth that can disengage for differential action. It is either locked or not, no slipping. They are a seriously heavy duty unit, I have never seen one fail.

If it had clutches I figured it be them sticking, but with the gov lock I don't think there' any clutches

Yes there are, just like an "old school" posi, just "improved" (not) with the spur gear mechanism. It is supposed to apply more pressure to the clutches when needed. They never "Lock" up though, the name confuses people.

[benoit454]

hmmmm so they do have clutches in them?

Good I bet that was our grabbing feeling, needed them lubed up so they'd let loose and move freely, I hope so anyways.

Reason I asked was we had a 76 with a posi and it was 12 bolt and you can clearly see the clutches in it, but this 84 10 bolt all I seen was the big block between spiders and those pins in between that flip open or whatever.

[James McClure]

Chris: They do have clutches, Jim

[mhicks]

I have a 2001 Jeep and there was a horible growling noise coming from the rearend area. I talked to a mechanic he he said do the the dealership and get the additive and it will fix. Went there, done that and fixed the noise withing 45 seconds of driving. I am so glad it turned out.

[benoit454]

that's what I'm hoping about our thump we have and lerching problem, that the additive will fix it.

Haven't had time to drive it yet, cleaned it up the other day, done the rear end oil change and inspection before that, new shocks on the front today, air shocks one day when I get off work this week or weekend, maybe take it to work one day this week, not sure.

[84 400]

Yeah i had one on my 85 C10. that truck would not break the tires loose on pavement ever! but in snow it was alot of fun to spin around in. I changed my rear diff fluid and it solved the clunk/click/chirp noise. I did not use additive. I bet yours will be back to normal with fluid and additive change.