Changed rear diff fluid

[Meccanoble]

I Changed and wanted to share my experience for others interested.

All bolts were13 mm. Fill bolt 3/8 ratchet naked. Did not lift truck nor remove spare but job would be easier if you Did. I followed video below but my fill bolt was on front plate of diff.

I had most trouble with top bolts but extender helps.

I also bought new gasket from chevy for about 33 dollars and looks very different from video. Better quality. Old one didn't need too bc re replaced at 128k miles but played it safe. Used green diff sealant on front plate side for easier cleaning during future changes among with white thread bolt sealant. Used mobil1 75w90 from pep boys.

Waited hour after bolting everything back up before refilling. Used red pump purchased from Amazon but with tire off, you could squeeze fluid in most likely.

Torqued bolts to 20
Torqued fill bolt to 25

Checked for leaks. Let idle for 5 minutes. Slow test drive around block and went harder later. Overall car drives the same but never really floored it so not sure if there is a difference. Monitoring gas mileage.

Overall, easy job.

Question, i wanted to change all fluids. Already changed tranny, engine, diff. All that's left is transfer case? Someone said there are 2 differential?

 

[bigrhino]

Thanks for sharing.

 

[ta07hoe]

Yea there is the front diff and transfer case.

 

[Goodinblack]

Part number for gasket?

 

[mizzouguy]

Would also like part number. Looks like a nice rubber/metal combo.

 

[Meccanoble]

When I called Chevy, they asked me how many bolts were on my diff. I believe there is a 10 bolt and 12 bolt diff. I had the 10 bolt one. I still have the receipt somewhere. Will try to update thread with part # if I find.

Regarding front diff, assuming it uses the same type of diff fluid as rear? I mainly drive on 2WD so front diff and transfer case is probably only used during Auto or 4WD?

 

[Meccanoble]

I've been researching and cant find anything on 2007+ tahoe front diff. Any feedback or videos? I'm not sure what is the diff and what is the transfer case.

 

[MichaelSE]

I've been researching and cant find anything on 2007+ tahoe front diff. Any feedback or videos? I'm not sure what is the diff and what is the transfer case.

So if you follow your front wheels to the CV axles to their yokes, they'll be attached to a large piece that looks like this:



That's the front diff. The drain and fill plugs are on the drivers side, and it'll take about 2 quarts of 80W-90. Even if you mainly drive in 2wd, it's a good idea to change it since the gears are still spinning (just not under load).

Follow the driveshaft back, or just follow your rear driveshaft forward, and it'll connect to the transfer case, which is bolted to the rear of the transmission. It looks like this:



I'm not sure where the fill plug is on this, because I still haven't got around to doing it, but the drain plug is on the bottom. Since yours is a 2011, it'll take 2 quarts of Dexron VI, the same as the transmission.

 

[Meccanoble]

EXTREMELY HELPFUL! Thanks! I bought the 5qt jug of ATF. Will return and get 2 small jugs and that 80W90

 

[Meccanoble]

Question, been researching trying to find synthetic 80W90 gear oil and its like impossible to find in a local store. Best I found was a blend at O'Reilly. I wanted to go synethetic to improve chances of better gas mileage and better oil. Am I doing this right? What 80W90 do people use in synethetic? Everything I find locally is conventional and assuming I should not be touching the 75W140....

http://www.oreillyauto.com/site/c/detail/VAL3/280/N2367.oap?ck=Search_N2367_-1_-1&pt=N2367&ppt=C1985