Is there a good way to change the fluid on a 2022 Duramax and is it ok to go with 668?
2022 Allison fluid change?
- Thread starter 68ss
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Fluid for which component
Guessing Allison 668 spec fluid? If so, spun this into its own thread in Trans Talk.
I would imagine the procedure would be the same as we've always done, wouldnt it? Hoot method or drain/refill/drive twice?
I would imagine the procedure would be the same as we've always done, wouldnt it? Hoot method or drain/refill/drive twice?
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Can’t do the hoot method, trans lines come off the trans together and there is a thermostat in the valve body that won’t allow flow.
Drain and fill a few times is the simplest. I’d suggest replacing the internal filter as well though.
Pull the large hex bolt on the pan to drain it (the little bolt is for checking level). To refill, you have to do it through the side of the case through an npt plug. Fill it, get the trans up to 170*ish and pull the little bolt on the drain plug while truck is running. Let it drain till it stops. Then put the plug back in.
I’d suggest sticking with dexron ULV. The tes 668 is Allison spec for their transmissions, this 10L1000 is not theirs but got their stamp to use in our trucks and be called an Allison. A thicker fluid is not a good idea for this trans (unsure if that 668 is or not)
Drain and fill a few times is the simplest. I’d suggest replacing the internal filter as well though.
Pull the large hex bolt on the pan to drain it (the little bolt is for checking level). To refill, you have to do it through the side of the case through an npt plug. Fill it, get the trans up to 170*ish and pull the little bolt on the drain plug while truck is running. Let it drain till it stops. Then put the plug back in.
I’d suggest sticking with dexron ULV. The tes 668 is Allison spec for their transmissions, this 10L1000 is not theirs but got their stamp to use in our trucks and be called an Allison. A thicker fluid is not a good idea for this trans (unsure if that 668 is or not)
Well, that right there shows how much Im out of touch with these new Allisons. Thanks James for that info!
James is right except I’m not sure what drain plug he is referring to. All the 10L1000s I’ve worked on only have the level check plug. Also the fill plug is a pain to get fluid in as it’s right by exhaust. Requires a pump of some sort. I wish it was all like the original Allisons still.
I've read where the GM fluid is recommended b/c the aftermarket fluid is thicker and leads to issues.
Ah shit that right, I kept thinking it was dual purpose like some zf trans
Sorry. You’re right I was asking about the trans fluid. I have a friend who asked me about it and I said I don’t know how todo it or if the 668 is the right fluid. On my 07 the process it easy. Don’t know about the 2022.
thanks for the reply’s
thanks for the reply’s
Yeah the 10 speed changed to the Ultra Low Viscosity fluid. They did it for mileage and temps but now everything inside is designed around it.
Also, don’t let reading that the big aluminum block for the trans cooler lines on the side of the trans is “the thermostat” for the transmission. It’s not. The thermostat is housed inside the vb. That’s just a support block for the lines and connections. Does nothing else.
Mike and I thought it was the thermostat too till we pulled it off. Then when we got into the VB, we found the thermostat. Mines been “disabled” because he’s seen them fail and stick closed. Plus I’m in az and too cold doesn’t really happen out here lol
Would like information on how you disabled the T-stat in the VB. Is it complicated and did it require any "special"parts? Living in TX, the number of times a decade where the trans stat would be beneficial are countable on one hand starting with freezing temps this week.
Good info Chevy1925 (James) about the thermostat. I have been looking for someone who can answer that question about the thermostat for a couple months now. I wanted to do the Hoot method on my 10L1000, but sounds like you have to get into the guts to get to the valve body. I would be ok with deleting the thermostat too, but how difficult is it to do this? Is it a mechanical delete, or can it be done with electrically with programming?
I honestly do not remember how to change it in/on the VB. It’s been 3 years since we did it and at that time, Mike, Jon and I were installing one of the first vb kits from ratiotek. We were very focused on that and Mike threw out the little tidbit of “oh there is the thermostat, these fuckers can stick and cause an overheat” to which I said “how do you eliminate that” and he proceeded to show me you reverse the location of the spring and plunger so it just has full flow. It’s a yellow plunger and I believe it’s similar to the 6l90