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Yes, but in the summer trans temps towing in stop and go or city driving can get over 200 degrees. About a month ago I installed a trans cooler thermostat bypass made by Linco diesel and trans temps are back to normal. LDP L5P TRANS COOLER BYPASS VALVE
He mentioned something about reinstalling OE for cold weather operation. I wonder how cold it would need to be to have to reinstall?


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What would the cost be to up grade to the new 10 speed? That is once it’s out and available to the public.


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Well I know of two of the 10 speeds warping two sets of clutches so far and a replacement built to hold extra power is no where as do able as the 6 due to it being drums and not the same designs as before. They are machining drums and shafts to fit more. All the hard parts have both GM and Ford numbers stamped on them the biggest difference is fluid and clutch preload and shift strategy.
** RevMax is building a prototype transmission for someone I know that broke the ten speed with added power.

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Any update on this? Feeling like a bought a $50k used lemon.
 

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Well I know of two of the 10 speeds warping two sets of clutches so far and a replacement built to hold extra power is no where as do able as the 6 due to it being drums and not the same designs as before. They are machining drums and shafts to fit more. All the hard parts have both GM and Ford numbers stamped on them the biggest difference is fluid and clutch preload and shift strategy.
** RevMax is building a prototype transmission for someone I know that broke the ten speed with added power.

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Do the HD 10 speeds share parts with the LD 10 speeds?
 

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Well unfortunately I have the known “chuggling” issue on my 2019 L5P Duramax. The issue has occurred half a dozen times and the truck only has 1,800 miles on it. It always happens in 3rd or 4th gear under light acceleration. It feels like the engine loses fuel for a second causing deceleration, then gets fuel for a second and accelerates, the loses fuel again and repeats this half a dozen times before it goes back to normal slow acceleration. For all I know it could be transmission related vs motor related. No dash indicator lights come on when this occurs. Local Chevy dealer is no help. Dealer service personnel told me if no dash light indicator lights come, no code is thrown, and there is no service recall / bulletin on file (they checked and no 2019 service bulletins) ... then I should call the GM Customer Service 1-800 number and log a complaint. Did this today, they logged the complaint, gave me a case number, and told me a senior advisor would contact me in 2 to 3 business days. Should be interesting to see what they say. Will update this post after they contact me.
Do you also get the OnStar notifications? I get three of them. They are telling me it is a fuel injector and my does not go back to normal. I have to take it in. Just wondering if it is the same thing?
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If you’ve been running this for awhile, do you have any feed back?


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I've been running an EPC fooler for a few thousand miles now with no problems. Im also running the Wcfab trans bypass plug so I don't notice any increase in temperature. Runs 70f over ambient all the time.
 

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Just throwing this out there.
I also have a 2018 1500 HC 6.2L with the 8 speed and 31K. I have it in the dealer now to have a TSB done for the exact problem all of you are having with the chuggling at lite throttle. Mine will usually do It after it warms up and going up a slight hill. Shakes until you add or reduce power. The cure for mine at least is to flush and refill trans with a newer type fluid. GM says some of the trans in 2017/2018 models have a fluid that seems to like moisture and causes the problem.
We'll see when I get the truck back in a few days.
Maybe the same fluid is in ya'lls trans? Never heard of the problem when running the 295 fluid in the Allisons- does the new 10 speed use the 295 fluid?
 

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Discussion Starter #50 (Edited)
Do you also get the OnStar notifications? I get three of them. They are telling me it is a fuel injector and my does not go back to normal. I have to take it in. Just wondering if it is the same thing?
Thanks
Never got any OnStar notifications.

When I purchased my 2019 new, it only had 7 miles, and I avoided any hard acceleration during the first thousand miles. Had the “chugging” issue occur randomly all the way up to 17k miles when I installed my 4 inch differential drop lift kit and 35 inch tires. As soon as the lift / tires were complete and I upgraded the weaker steering components ... I changed out the Dexron VI transmission fluid + internal filter (change out the external filter every other oil change) and replaced the fluid with Mobil‘s TES-295 ATF fluid (double drain and fill) similar to the more commonly known Transynd. Also installed my Banks Derringer, Ram Air CAI, and 4 inch DPF-back exhaust at that time as well. I then took it down to the dealer and had them do a free transmission relearn since the truck was still under the 3yr / 36k warranty. Then immediately as I left the dealership accelerated at 1/4 throttle thru all the gears. Then immediately accelerated at 1/2 throttle thru all the gears again. Then immediately accelerated at 3/4 throttle thru all the gears. Then immediately accelerated at full throttle thru all the gears. Repeated this whole process twice. Then drove my truck like I normally do ... fairly aggressive. Never again did I experience the “chugging” issue. Since I changed so many different things not sure which one fixed the “chugging” issue. All I know ... it’s gone. Hope this helps.

Side Note: I am convinced the truck shifts smoother with the fully synthetic transmission fluid vs. the factory Dexron VI fluid.
 
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I picked the 1500 up this afternoon after the trans fluid flush and refill with improved fluid. I can tell the difference in shifts and no more shuddering at all.
Glad you got yours fixed UT and I would bet money it was the fluid. Probably same stuff I had in the 8spd
 
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