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Hummer H2For those who like a little more gleam to their Hummer, the H2 offers a similar rugged look as the H1, but as a lower cost, and with more added features, making it almost a massive luxury SUV.
You are confused. Frothing problem is when your trany, motor, T-case, or diff fluids look like.....foam.
The tiny air bubbles in your video are normal, and not an issue. The "froth" is actually the very thin line of larger bubbles on top of the liquid in your photo #2.
Same as froth on your Starbucks coffee. And photo #2 shows very little frothing.
Frothing problem is something completely different to what you think it is, as in most of the liquid becoming foam, and then components being starved of oil.
And you know exactly what I mean, so stop being a troll.
Some people think Hummer owners are a-holes. Why give them more ammunition?
I like my beer straight out of the bottle, if I pour into a glass I get frothing.
Bottom line, differential fluid will froth and increase in volume when heated. Only check differential fluid level cold, after the fluid settles from frothing+make sure to check condition of the vent tube.
Still my go to fluid:
You are confused. Frothing problem is when your trany, motor, T-case, or diff fluids look like.....foam.
The tiny air bubbles in your video are normal, and not an issue. The "froth" is actually the very thin line of larger bubbles on top of the liquid in your photo #2.
Same as froth on your Starbucks coffee. And photo #2 shows very little frothing.
Frothing problem is something completely different to what you think it is, as in most of the liquid becoming foam, and then components being starved of oil.
And you know exactly what I mean, so stop being a troll.
Some people think Hummer owners are a-holes. Why give them more ammunition?
I just checked my paper copy of the 2007 H2 Service manual (aka Workshop manual for UK dwellers).
It contradicts the owners manual, by a very large amount of fluid on the rear.
2007 Service Manual:
Front differential level: 0-10mm (0-0.375") below fill hole. (= 0-3/8" below fill hole). Page 7-15. Exactly 0.375", LOL!
Rear differential level: 0-10mm (0-0.4") below fill hole. (= 0-3/8" below fill hole). Page 7-104
Looks like the common knowledge info applies in this case. Fill cold till it starts leaking out of the fill hole.
Where did you get your fill info from, owner's manual? If it was a shop/service manual, then what year?
@oceanbrave Unless your MY is different from the 07MY, looks like owner's manual is wrong on this one, and having a fill level on the rear that is 1+5/8" below the fill hole will starve the diff of gear fluid. I checked, and that is draining a LOT of the fluid (estimating 1/2L or a whopping 25% capacity of the diff)
Indeed mine is an 05
Just checked both my 05 manual and the GM Service manual, they agree, here's a snippet :-
Did GM change diff's ?
My mechanic filled mine last time, he put 2.5L in (to the hole, I measured what came out) I put 0.5 less (5/8" below hole, finger tip) so the 5/8" equates to an extra 0.5L
Just checked the "04" , "05", "06" and "07" owners manuals, they all have the same diagram and quote the same figure as above, something is off somewhere...
My fate is in the hands of the mechanical God's on this one, this would be a big mistake by GM ...
Here you go. Proof right from the General himself, right out of his 2007 H2 factory service manual.
So what does this mean?
Who is wrong? Bet that owner's manual is VERY wrong.
BECAUSE it would be very difficult to measure the level 1+5/8" below the lip unless you had a special bent tool. So that can NOT be correct.
Point #7 and Point # 8 says it all. Fill till the stuff runs out.
No need to use the "finger dip" method mentioned above, if the workshop manual is right.
It's a dichotomy, but you're probably correct on this one.
Owners manuals 04,05,06,07 all say the 5/8" to 1+5/8" etc (consistent) but eventually found the Rear Axle Lubricant page in the electronic GM Service Manual (not listed if searching for "Differential") which quotes 2.6L / 2.75Q
Which is almost exactly what I drained-out (2.5L)
Must admit, I was puzzled over the finger-top method, how could anyone determine the level and with what tool, as you say?
Owners Manual Figures
Between 0.0" to 0.625" the error is 0.375L, approx. 14%, but worst case is 0-1.625" (0.6L as measured) so approx 23% !
Service Manual Figures
Between 0" and 0.375"the difference is 0.14L or approx. 5%
So you're point is valid, also "to the drain hole" means you can't overfill, but the other way you can under-fill, also poking objects inside the casing is risky.
You make good points @oceanbrave. I will bring this up with my GM dealer next time I am over there, and see what their latest electronic shop manual says. Those are updated regularly. But I think I already know what it will say (same as your electronic copy).
To further confuse things, the rear end capacity is quoted as 1.9L and front at 1.2L. But as you have witnessed, you pulled 2.5L out of yours, which should have been to the hole edge.
That indeed means a discrepancy of 0.6L or 24% as you say. So are they quoting the 1.9L at the minimum -1+5/8" level in the owner's manual? Must be.
Then your electronic copy quotes 2.6L, which would take us close to the hole edge, consistent with the service manual instructions to fill to the hole edge.
So again, I am going to say that 1.9L is wrong, and 2.6L is correct.
What a mess!
I too am surprised that an error like this would carry over so many years of owner's manuals.
Maybe in practice, it does not really matter if you overfill or under-fill by 25%? If it did, we should be seeing a lot of bad rear ends popping up on the H2s.
Is there a GM mechanic on this forum that can dig into this thru their GM Tech Assistance line? To get us a definitive answer. I am sure GM does not care at all at this point, as they washed their hands of this vehicle a decade ago, but it would be nice to have a definitive answer.
10-19-2021, 03:37 PM
