2024 gmc hd 6.6 duramax
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You might get the first couple of oil changes free. I got 4 with the 2018 LML and 2 with the 2022 3.6 Acadia.
On top of that, I always drain the factory fill around a thousand kms. (600 miles)
Your factory fill is likely 5W40. Petro-Canada has the ATF contract for Allison 668 fluids (Afton Chemical), I'm not sure about the
10 speed.
GM tends to under fill their diffs and tc cases imo. You might want to check those levels. They say 12mm (1/2") below the fill plug,
but most guys fill to the lube is running out.
Which 15w40? The one that everyone says is second best.
On top of that, I always drain the factory fill around a thousand kms. (600 miles)
Your factory fill is likely 5W40. Petro-Canada has the ATF contract for Allison 668 fluids (Afton Chemical), I'm not sure about the
10 speed.
GM tends to under fill their diffs and tc cases imo. You might want to check those levels. They say 12mm (1/2") below the fill plug,
but most guys fill to the lube is running out.
Which 15w40? The one that everyone says is second best.
Factory fill is Delvac 15W40. Any decent CK-4 oil will serve you well. Duramax's are easy on oil. 2 of mine run Delo 5W40 year round and the newest one I'm trying the ultra low ash Delo 600 ADF 15W40. All are on extended drains and all sample well.
Userfriendly is right, diff levels are supposed to be 0.4 inches (10mm) below the fill plug with a level truck and oil hot enough that it will fall back down into the diff fairly quick. I'd advise against spill filling to the plug level. Grease it right away, they are pretty dry. Most zerks took 15 to 20 pumps on my new one.
Trans is Dexron ULV. Not a lot of options out there. Transmission is not user friendly from a service standpoint, and there's no dipstick to check the oil. Be careful what you put in it for oil if you do service it yourself. Lots of places say their universal or Dex6 fluids are okay, they aren't. The transmission is programmed to operate with the thinner ULV (~4.5 cst) fluid. It has a MASSIVE cooler on it so temps aren't an issue. I haven't seen mine over 155F yet.
Congrats on the new rig!
Userfriendly is right, diff levels are supposed to be 0.4 inches (10mm) below the fill plug with a level truck and oil hot enough that it will fall back down into the diff fairly quick. I'd advise against spill filling to the plug level. Grease it right away, they are pretty dry. Most zerks took 15 to 20 pumps on my new one.
Trans is Dexron ULV. Not a lot of options out there. Transmission is not user friendly from a service standpoint, and there's no dipstick to check the oil. Be careful what you put in it for oil if you do service it yourself. Lots of places say their universal or Dex6 fluids are okay, they aren't. The transmission is programmed to operate with the thinner ULV (~4.5 cst) fluid. It has a MASSIVE cooler on it so temps aren't an issue. I haven't seen mine over 155F yet.
Congrats on the new rig!
Excellent post. There's a few zerkies under the front shield most people never service. The 5w40 ff could be a Canadian thing.
I haven't looked at the 10 speed yet. On a Ford Escape transmission there's a plug that you take out. With the engine at idle,
fill the transmission until the atf overflows and runs out. Obviously one of Ford's better ideas and their imput on the 10 speed
not having a dipstick.
There could be a fill to overfill plug on the "Allison Branded" 10 speed. ???
You're right about the ATF temperature. It takes a lot of hard climbing up a mountain pass on a hot day..... and I've never seen
90C.
edit; There's already transmission program "upgrades" for the 10 speed that increase line pressure and reduce the "fuel off"
time while shifting. IMO the HP & TQ race is hard enough on the tires and drive line without chirping the tires on every shift.
Add that to the lifted bro-truck with 37s and increased driveline angles and the weak link will break.
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There is a spill level plug on the bottom of the pan (connected to a standpipe inside) and a fill plug on the R side. Stupid thing is, GM says the fluid temp has to be at 170F to check it properly. It's painful to sit there and torque stall it that much to get the fluid that hot. So far I like the transmission except servicing it, then I'll take my 6 speed Alli's every time.
Weird about the 'upgrades', there is literally milliseconds of defuel per shift. One of the benefits of the ULV is the shift timing on these things is lightning quick. One of the reasons I mentioned the ULV is if you use a thicker 6 or 7 cst fluid in these things they slip and shift like crap when its cold. It's the only HD 10 speed issues I've seen at the dealer so far. But hey, the aftermarket loves to sell solutions for problems they dream up.
Weird about the 'upgrades', there is literally milliseconds of defuel per shift. One of the benefits of the ULV is the shift timing on these things is lightning quick. One of the reasons I mentioned the ULV is if you use a thicker 6 or 7 cst fluid in these things they slip and shift like crap when its cold. It's the only HD 10 speed issues I've seen at the dealer so far. But hey, the aftermarket loves to sell solutions for problems they dream up.
Defuel has never been mentioned before on bitog. I first read about in the 2013/14 Corvette engineering summary handed to me from
my daughter's father in law from The Motor City. It was an 8 hour read from the rear view mirror shape and placement to
cylinder heads and swirl inducing bla bla to how many piston shapes they tried.
Near as I can tell, the 6 speed 1000s are impervious to atf choice and run on anything they are fed.
Ya, the 6 speeds love a 6 to 7.5 cst fluid....Dex3 or 6 or TES 295 or the newest 668 fluid. They de fuel more than the HD 10sp, which helps them live forever like they do. Time will tell if the 10's are gonna live as long.
I forgot to ask you what's in the big green truck? A 16x645 EMD?
That's what was in it ya. As it sits now the engine is removed.
I took the liberty of posting the oil requirement for a 6.6 Duramax from a 2023 manual. Enjoy.
Yes, 5w40 for below 0 F. Gotta start this beast in Edmonton.
4WD
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For the difference in cost - might be worth seasonal changes … 15W40 Delvac is now made with EHC …
Neil Young said "Portage & Main 35 below".
Been there, got the t-shirt.
A sales manager at a dealership told me that when trucks arrive on the auto carriers, the Duramax will start, but the Ram Cummins
won't even crank over @ -30C. They have both brands on an adjoining lot in Brandon, MB.
I've seen uoa's on the D-Max FF. The KV100C viscosity, usually around 95 looks too low for a 15w40, which are typically 105-120 @ 100C.
4WD
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