SabrToothSqrl

So I'm thinking that at 100,000 it's time to replace my transfer case fluid and diff fluids. (and maybe the transmission?)

Transfer case is 1.6 QT of DEXRON-VI, so 2 quarts needed.

Front diff says 80W-90 and rear says 75W-90 synthetic.

I'll most likely just go synthetic for both.

Anyway, what's the diff capacity of each? anyone know? 2009 Tahoe LTZ 4x4. Page 5-122 of the manual is capacities, but oddly the differentials are missing?!

I'm guessing 2 quarts each, but that's just a guess... it's been a while since I've done this on my Wrangler long ago, and the Mazda a few years ago.

in2pro

I don't have the 4wd but I just did the rear diff with M1 75W-90 Synthetic Gear Lube it took about 2 and 1/2 quarts... Be sure to get the gasket as the old one will most likely not be salvageable despite what the factory manual says

I jacked the rear end up on jack stands and I was able to comfortably sit under the rear of the vehicle to do the work. The rear sway bar and a cross member are kinda a PITA but its workable..

Oh and make sure you have lowered the vehicle back to level ground before doing the final top off.... I also took the opportunity to use an air needle scaler to clean up the diff cover and repainted it black while I had it off...

I covered the gears and housing opening with paper towels while I scrapped the old gasket off to prevent pieces of it getting into the housing and used brake cleaner to do a final rinse of the gears and housing prior to re-assembly... ( do let it dry out before putting back together)

I used a Permatex Ultra Black in addition to the gasket...

SabrToothSqrl

I'm thinking of going the lazy route and just changing the oil... I'm not sure the use warrants popping the cover, although it would be nice to inspect the gears...

So I'll need 3 quarts to use 2.5 of each... good times.

Does the Tahoe have drain and fill plugs or will I have to pump out the old? Yes I'm being lazy!

Anyone have any videos / experience draining and refilling the transmission and or replacing the transmission filter? I found one for the 06 Tahoe, but the 09 would be a different transmission.

I'm guessing that one drops the transmission pan, and the filter sits above it?

http://shop.advanceautoparts.com/web...hedFrom=header

Seems to be quite the price range of products here... Watching the 2006 Tahoe one it looks like the 09 6 speed would be very simliar with the metal ring seal at the top of the filter and it just 'wiggles' out.

in2pro

My diff did not have a drain plug so its removal of the cover or sucking it out...

As for the transmission , I had the dealership do it when I had it in for an oil change and state inspection... it was about $200....
After you read these instructions you may opt to go that route... I would bail at step 5...

in2pro

You might also consider replacing the tranny pan with one that has a drain plug even if you have someone else do it, a new pan with a drain plug is less than $50....

SabrToothSqrl

You really have to remove the cat?! None of the videos show that.

While I'm under it doing the diffs, I'll take a look. thanks for the instructions, thats about the same as the videos show.

Yea, I have a $5 harbor freight hand pump I can use to suck fluid out. Ordered the fluids online, will pick them up tonight.

I'm going to be busy until at least Tuesday night too.

Also managed to run my boat into a rock and F up the prop and skeg... good times.

in2pro

I haven't looked under the truck to verify, it could simply be for ease of access and if you are willing to work around it, its probably do-able with some level of frustration...

SabrToothSqrl

you want frustration?

my raw water pump went on the boat (boats use 2 water pumps).

The impeller shattered. (rubber) and sent chunks into the cooling system. (awesome possum)

So being stupid (and cheap) the 'raw water pump kit' was like $70. (not much in retrospect).

So I bought a $20 impeller. non OEM. the OEM lasted 12+ years, last non oem lasted 4 years.

Replaced the impeller, still over heats. *keep in mind each test means dragging the boat to the lake... which is easier than dragging said water to the boat.

Acquire a OEM back plate, installed. Still over heats
Trace cooling line to the power steering cooler. Find 2 pieces of rubber impeller jammed in there. remove.
Replace impeller again
Still over heats. Temp starts normal and slowly climbs under load to overheat levels, impairing performance, and obviously maybe killing engine (OMC 460).

Next, test thermo stat, works fine. reinstall w/new gaskets.

Still overheats. Winterize the damn thing because I give up. Also smoked a wheel bearing, so had to replace all 4 of those.

Break down and buy housing and new gaskets for raw water pump.
New thermostat because the one from 1990 is 25 years old... so for $20 why not?

Ran it last night, and temp was DEAD ON had I not smacked a $700 prop against the ramp, it would have been a terrific night.

Performance was dead on now (it varied a lot with temp).

So that $70 kit I was avoiding buying... had the impeller, housing, metal cage, gasket all in one kit.

I may just buy that kit to have on hand next time.

Sometimes going cheap or piecing it together just ends up being death by 1,000 paper cuts.

Now I know why dealers just replace assemblies. Troubleshooting and having a customer come back 3x for the same issue just causes more stress. On my Wrangler, they didn't replace a blown diff, they just swapped the whole back axle! (warranty).

and this is also why I don't rebuild carb's on old jet skis when working on them... $400 for a new set means they work 100% right first bolt on. rebuild is $2-300 and who knows what you missed...

{tpc}

Well my personal info comes from as it relates to a 2007 with 4wd. I've just recently done all the fluids.

The front and rear diff's were not to bad. For the front, remember to take the fill plug out first, so you know you can get it out. For the back, buy the gasket and use a little ultra black as has been suggested. I think both took a little over 2 qts to fill. I used one of those cheapy hand pump things you can attach to the bottle.

Getting the rear diff cover clean for the new gasket sucks. The cover isn't bad, but half is stuck to that, the other half stuck to part on the truck...which is a pain. Pretty easy to fill both, essentially its a fill till it comes out kinda deal, at least its what I did.

Transfer case on mine was the easiest part. Except I have to use autotrack ii fluid there..and can only be bought at the dealer, but I had 2 qts on hand.

Transmission fluid. Now here is the tricky part. I know you don't have the 4l60e, so this may be totally unrelated. But for mine, GM was nice enough to put an exhaust crossmember right underneath near the front of the pan. It LOOKS as if there is clearance, but there isn't. I was dropping the pan to replace the filter and gasket as well in my case. So step one, I used the truck to pump out about 4-5 qts of fluid froma disconnected line at the tranny cooler.

Then I went to take the pan down. All bolts off, hearing a bit of dirt here or there...can't get the pan down. X-member in the way. Shift cable bracket in the way. Can't put it back together because might have dirt in it. Can't get shift bracket off because screws on top behind a bunch of crap..large torx bits with copious amounts of threadlocker. I almost gave up and had it towed to the dealer. Dropping the exhaust wasn't on my plans, and jacking up the tranny after removing the rear mount does nothing.

Finally found a suggestion to bend the bracket out of the way. I did not like doing this but it was necessary. The front driveshaft runs right next to it so I couldn't bend it too much...just to the driveshaft and clamp it down. After I did that I was finally able to twist the pan just enough to get it to drop out.

Sure enough, wasn't any dirt in the pan...but I couldn't tell. So I finally got the job done. Something like $35 for the filter/gasket kit and $50 for 12 qts of dex vi.

Saved myself over $100 as the dealer qouted me $235 oe something like that to do it.

Took me 2 full days sun up to sun down messing with it. Next time, I'll pay the $235.

tech2

to drop the trans pan have someone pry the ypipe down with a pry bar while you slide the pan and gasket off. You don not need to remove any y-pipe bolts, brackets etc.
if u were to see it done; its a 5 second step. Next time I do one i'll post a video.