Detroit locker

[Caminuvik]

I ended up with a 77 blazer, I was told that it had a Detroit locker. Another person said that they did not make a Detroit locker for a GM 12 bolt. Does anyone know which is correct. I am more into 3/4, 1 tons than halves, Thanks

[mikebte]

Prolly referring the the G80, it’s a Detroit locker. I think in 77 it was optional. GM really pushed this and still uses it today. Most older rear ends I have seen with the G80 have been broken and all the teeth are missing or in the bottom of the housing. But older trucks saw more farm use then modern trucks. Best to remove the cover and have a look see.

[Caminuvik]

Well that is interesting, I thank you for your knowledge and reply. I am working on a septic system and a well, trying to get a plow truck running before snow, though I am really curious now (and now know what it looks like) but do not have the time at the moment nor the desire to lay in the mud to check. But its on the list. Thanks

[sweetk30]

2nd poster posted a link to a posi listed wrong as a locker . yes its a eaton/detroit unit .

then the g80 is NOT a detroit locker . its a posi that locks in when 1 wheel spins to fast . and they are knows to go BOOM in 10bolt / 12 bolt / 14semi float axles way more then in 14ff axles .

only true way to tell is pull the cover and take pic and post up . also good time to service the rear end oil .

i know whats added in to my axles each one of them as i have put them in there . thats how you know for sure .

[mongocanfly]

My bad...I didn't even see the pic was wrong until you pointed it out k30...my network is running really slow for some unknown reason and i didnt see it was wrong...so I deleted it...
But yeah....pull the cover...

[sweetk30]

mine a bit slow tonight also .

figure i would just clear it up if you missed it .

[Caminuvik]

Well guess I will pull dif cover during a hopefully break in the rain tomorrow. 🤐 Now if i understand there could be a true locker in there, -they are made?

[Matt Man]

They do make detroit lockers for the gm 12 bolt truck rear end. Is the truck in running condition? If it is you can google driving characteristics of the detroit locker, they make there presence pretty easily with the clunk when you let off the accelerator. My 81 has one installed in the 12 bolt.

[Caminuvik]

No, not running, but time, money, parts, and knowledge it could be, unfortunately I have little of those. Going to have to learn to post pictures, unsuccessful attempts so far.

[mongocanfly]

Here's how to post pics....http://67-72chevytrucks.com/vboard/s...sting+pictures

[mikebte]

Here is what it may look like if it has the G80.

[Caminuvik]

Great picture - will look tomorrow even if it snows. I was doing ok with the picture posting, but got the "security token missing" the thread stated that was a too large of picture. Now, I need to figure out how to reduce size of a picture in my Gallery. Just never seems to end. 😂 Thanks

[Caminuvik]

Picture of the Blazer diff.

Feel good as I have successfully uploaded a picture. Could someone tell me what it is and what I need to use to replace the diff oil. Thanks

[mongocanfly]

Looks like a open diff....can you get a better pic of the center of the diff where the spider and side gears are?
This area

[mongocanfly]

I can't tell what these are outlined in red

[Caminuvik]

A better picture, I think.

[Caminuvik]

A better picture, I think.

[mongocanfly]

Spin the diff over and get a pic of the opposite side of the carrier...

[Caminuvik]

opposite side

[mikebte]

I us delo that I can pick up at truck shops cheap, but I think they have it at auto parts stores as well. Service intervols on delo is way higher than most others. Or at least that's what it says on the bottle. And being the trucking industry the oils get a lot of testing and research.

Sorry, many years in the trucking industry. I even run Alison Transmission fluid in my GM truck.

[Killer Bee]

good pictures, sure looks like a G80 Gov-Lock [governor locker] or affectionately called Gov-Bomb

lots of good illustrations and videos out there on these.. and as mentioned, they are not the same as a Detroit Locker..





I wouldn't just willy-nilly pour TES-295 in my automotive trans without checking specs..

modern automotive ATF has gotten real slippery with non backwards compatibility.. <-- pun intended

as for differentials, same issues arise, better to check specs of any oils you're planning to use..

must consider weights, friction modifiers, soft parts compatibility e.g. seals, gaskets, clutches, sensor wiring, etc..

'high performance' for some applications may = 'no performance' for others..

good luck y'all!

[Caminuvik]

I thought so also, but noticed an extra bar in the Blazer one, and in the picture of G80 on the right is that a clutch pack? Doesn't seem to be one in the Blazer diff. Could this just be an open diff?

[Killer Bee]

lol, I edited my post after noticing something a little different there.. oops

that deserves closer inspection and/or comparisons to known stock units..

I know little more about these than what they generally look like and how they work..

other members above are much better candidates to answer that question..

good luck!

[mongocanfly]

Yep its a g80..govlok...youll need the correct lube for it....https://www.chevytalk.org/fusionbb/s...php?tid/256237

[Caminuvik]

Thanks, it been a great learning experience. I will drag it up and park it, thought it was going to be a bonus.