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Discussion Starter #1
I didn’t buy this truck new but I am wondering if anyone notices the RPM going a little higher between gears as it shifts? It almost seems like it slips a bit or something, I’m not sure if it’s the clutch in torque converter allowing some slip or not.

I’m guessing I’m hoping to hear that it’s ok and that it’s normal without a trans tune
 

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There is a possible known issue with the torque converters going bad...so...there could be that. Unfortunately. Just saying is all. I don’t notice my truck rev up between shifts. However, I have a trans tune, so.
 

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Discussion Starter #3
Ok thanks man, I just put nearly $2800 into the transmission so I’m not going to be happy if the TC needs replaced too after that had the truck for 7 days already
 

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My
I didn’t buy this truck new but I am wondering if anyone notices the RPM going a little higher between gears as it shifts? It almost seems like it slips a bit or something, I’m not sure if it’s the clutch in torque converter allowing some slip or not.

I’m guessing I’m hoping to hear that it’s ok and that it’s normal without a trans tune
My 2018 does this when going from 2nd to 3rd
It’s very noticeable
Only does it when under light load.
I believe it’s poor transmission programming.
I think it shifts way to soft. I would like to have a more positive shift.
 

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Discussion Starter #5
I’m about to put a tune on it soon so hopefully this will remedy the problem. Thanks for the reply
 

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Discussion Starter #7
Yeah it’s hard to say, the one I have coming is supposed to tune the trans as well so I’m curious to see how that goes.

I’m going to send you a pm if you don’t mind Oak
 

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The transmissions behavior is heavily dictated by the programming in the Trans Control Module. Both my engine and transmission are tuned, and the tuner (GDE) went through a few iterations of transmission calibrations. The original settings they sent had it shifting too firm, it felt like a dump truck, coming to a stop it dropped into 1st with a notable thud. Definitely no "mush" going on there. Later revisions were more civilized, it turns out that the transmission's "tolerance" can vary, so the same settings will be a bit abrupt in a "low tolerance" transmission and a little soft in another. Evidently my truck's tranny is a "low tolerance" number.

I theorize that GM made the stock programming "soft" so no transmissions would be rough for the end users, but that leaves a lot of room for improvement for any individual transmission.

After tweaking mine with various tune files, I finally found a combo that works really well and does not excessively slip. Even my tweaked setup will slip a little and be lazy if you feather the pedal and take off really easy though. Accelerating briskly seems to work better, feathering the pedal leads to a lot of slipping/flaring in the transmission. No need to floorboard it, but feeding the trans some torque seems to have it shifting better and working as good as it can. I recall my stock trans programming had a really slippy "dipsy doodle" 3rd to 4th shift no matter what I did though.

On a somewhat related note, there are plastic panels that block off the lower portion of the radiator where the trans cooler lines come in. I removed these with no apparent issues with the trans or engine temps even in winter - the trans seems to run about 15 to 20 degrees cooler per the DIC, running in the 170s instead of 190s in ordinary use. I have no idea why GM put those on there, they are not present in the gas models. The panels can be accessed through the grllle and yanked with a long needle nose pliers and pulled out the soft bottom rubber seal under the truck without taking anything apart.
 

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Discussion Starter #10
Thank you that makes sense, I will have to give you guys a report when I get my tuner and get my turn installed. I appreciate the reply!
 

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Same exact issue here. Noticeable slip from 2 to 3 under light load (particularly uphill). At the dealer now for other warranty work so we will see what they say....
 

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Discussion Starter #12
Keep us posted, it definitely seems like something in the programming what this guys are saying
 

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There is a possible known issue with the torque converters going bad...so...there could be that. Unfortunately. Just saying is all. I don’t notice my truck rev up between shifts. However, I have a trans tune, so.
There is a possible known issue with the torque converters going bad...so...there could be that. Unfortunately. Just saying is all. I don’t notice my truck rev up between shifts. However, I have a trans tune, so.
Would you please expand on your trans tune? I read most new posts, but if you have already done so, just tell me and I'll find them myself. I am 180 out from you on engine tunes, but anything to make my trans more durable would be well received.

Thanks
 

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Would you please expand on your trans tune? I read most new posts, but if you have already done so, just tell me and I'll find them myself. I am 180 out from you on engine tunes, but anything to make my trans more durable would be well received.

Thanks
I can’t say I’ve heard of anyone just getting a trans tune. But, I wouldn’t see why you couldn’t. I have my trans tune through hACKman Customs (sold through American Diesel Power).

I do not recall having a bad experience with my trans before the tune (I did have a slow to react throttle though) but since then, I do know I have no complaints with the tune either. Shifts smoothly at all speeds and under varying acceleration loads (pretty sure my wife only knows how to drive fast while I am more easy going). It may shift more stiffly/ abrupt if you really lay into it, but it should as it’s trying to shift fast to keep up.

What duken4ver said about varying tolerances of transmissions sounds viable, I will say I have only ever had 1 iteration of a trans tune from my provider. It would be worth getting ahold of ADP to see about a trans only tune.
 

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On a somewhat related note, there are plastic panels that block off the lower portion of the radiator where the trans cooler lines come in. I removed these with no apparent issues with the trans or engine temps even in winter - the trans seems to run about 15 to 20 degrees cooler per the DIC, running in the 170s instead of 190s in ordinary use. I have no idea why GM put those on there, they are not present in the gas models. The panels can be accessed through the grllle and yanked with a long needle nose pliers and pulled out the soft bottom rubber seal under the truck without taking anything apart.
Can you post a picture for me please?
 

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Can you post a picture for me please?
Here you go. No need to remove the front fascia, but this photo shows what is going on really well with it removed - the lower 1/3 of the radiator is blocked off by the two plastic panels, and the upper portion of the radiator has the intercooler in front of it.

I was able to reach through my Canyon's grille with a long needle nose pliers, pinch the panel's clip thingies and release them. Then just push the panels out the bottom past the flexible rubber gasket. The whole job took just a few minutes.

Have not noticed any issue at all with warm up of the engine, heater function or trans function this winter, and the trans definitely runs cooler in warm weather - I think 15 to 20F cooler. In frigid temps, the trans will get up to about 140F after awhile, cooler than before, but I don't think it presents a problem. The trans fluid heat exchanger coolant lines plumb into the lower portion of the radiator that is blocked off.

Fully warmed engine temp in warm or cold weather monitored by OBD Fusion on my phone remains steady at around 176F regardless of weather it seems, and the engine warms up the same with the panels off - pretty quickly while driving. The thermostat seems to do a really good job of warming the engine quickly and holding constant engine temps. In really cold weather, it is my habit to crank the seat heater to roast, drive off gently and leave the cabin heat off until the engine warms, which does not take long.

I don't see that the thermostat needs any "help" from these panels and the transmission works fine without them in cold weather. The extra cooling capacity without the panels might come in handy when working the truck hard in hot weather too, particularly for the transmission.

The radiator in our trucks does seem really efficient. Even choked off with all this in front of it, I have never seen the engine run hot, but the trans can easily heat up and get warmer (205F or so just driving around and not towing) than the 175F I prefer under those circumstances. Removing the panels seems to have solved that "issue" and gives more margin before the trans heats up past 240F. I know the trans fluid is OK at that kind of temp, but the life span of the solenoids in the transmission is shortened at sustained elevated temps.

8545
 

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My 16 slips HARD between 2-3rd... enough to piss you off. Feels like you hit a curb. Now it might do it 2-3 times in a week then it won’t do it again For 2 months. Very hit and miss. I notice it more when I’m at lower speeds like 35mph. But lose stuff in the truck.. like console, door pockets are bounced around.
 

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My 16 slips HARD between 2-3rd... enough to piss you off. Feels like you hit a curb. Now it might do it 2-3 times in a week then it won’t do it again For 2 months. Very hit and miss. I notice it more when I’m at lower speeds like 35mph. But lose stuff in the truck.. like console, door pockets are bounced around.
have you changed the transmission fluid? How many miles are on the truck.
 
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