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Posted (edited)

Question for you guys. For the most part I'm super happy with the 1500. Love the looks , int., and such but what I'm finding is its finicky with temperature. I'm noticing if its a decent day even 32 degrees she runs good once all warmed up. We are in a big cold snap today, tonight and tomorrow if - numbers. I had taken a ride to the gym at 430 and I had no problems. My drive consists of a main road then a highway for 10 minutes then another 10 minutes on a back road. Coming home the temp is 0 degrees with a windchill of -25. I noticed it a lot on the highway but I was getting major surging. Almost like a carburetor with dirty jets. The truck would be driving and surge ,run good then surge. I know cold weather reeks havoc on everything but I figured once up to temp there would be no problem. Seems in the cold the tranny has major dead spots between shifts and the horrible surge. Has anyone else encountered this and have an answer to what may be the problem?

 

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Edited by Jeff5347
Posted

Does this sound like the same behavior your truck has?:

 

http://www.gm-trucks.com/forums/topic/155198-rpms-fluctuating-when-accelerating-under-light-load/

or

http://www.gm-trucks.com/forums/topic/181145-2014-53l-6-speed-rpm-fluctuations/

 

 

A small amount of RPM fluctuation is normal. The TCC is allowed to slip a little even when locked up and causes the engine to sound like it's surging a bit.

 

 

A torque converter with an electronically controlled capacity clutch (ECCC). ECCC was developed to reduce the possibility of noise, vibration, or chuggle caused by TCC apply. In a torque converter with ECCC, the pressure plate does not always fully lock to the torque converter cover. Instead, the pressure plate maintains a small amount of slippage. In RWD 6-Speed transmissions, this slippage can range from 0-50 RPM. Full lockup (0 RPM slip) is still available on some applications. TCC may apply in 2nd, 3rd, 4th, 5th, or 6th gears. The specific TCC apply points and the amount of clutch slippage are determined by a number of operating conditions, including throttle position, vehicle speed, gear, as well as specific vehicle application. Transmission fluid temperature will also affect TCC apply points.

http://www.transtar1.com/TranstarIndustries/media/Transtar1/technical/bulletins/TLT-TC-035.pdf

Posted

From reading it sounds like that may be it. I didn't notice the needle movement like morrislee but I wasnt paying attention to it either. I drive this highway every day so I'm wondering if it is the super cold we have right now. I do 90 % of driving in the manual mode. M4 or m5 around town and when I jump on the highway upshift to m6 once I get up to 65- 70/mph. I haven't tried to see if leaving it in m5 on the highway or having the shift lever in D mode instead of M. This was at the approximate speed of 70 and I noticed it more once I had a grade to climb whether it be a slight uphill or more pronounced. I'll have to keep an eye on it and try leaving it in M5 to see if v4 or m6 is the culprit. At least this gives some info on where its coming from. Another thing and not sure if this is coincidence or a factor but I only notice this after installing my leveling kit albeit we haven't had this low of temps ( minus degrees) either.

 

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Posted

From reading it sounds like that may be it. I didn't notice the needle movement like morrislee but I wasnt paying attention to it either. I drive this highway every day so I'm wondering if it is the super cold we have right now. I do 90 % of driving in the manual mode. M4 or m5 around town and when I jump on the highway upshift to m6 once I get up to 65- 70/mph. I haven't tried to see if leaving it in m5 on the highway or having the shift lever in D mode instead of M. This was at the approximate speed of 70 and I noticed it more once I had a grade to climb whether it be a slight uphill or more pronounced. I'll have to keep an eye on it and try leaving it in M5 to see if v4 or m6 is the culprit. At least this gives some info on where its coming from. Another thing and not sure if this is coincidence or a factor but I only notice this after installing my leveling kit albeit we haven't had this low of temps ( minus degrees) either.

 

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I am starting to guess it is my air intake icing up, I cleaned and re-oiled my K&N air intake today, will see tomorrow cold morning.

Posted

Check for possible vacuum leaks while you're at it.

 

Made very sure that every hose is tight and also cleaned the throttle body.

 

Still happened this morning, so I just cleaned the MAF sensor with the CRC cleaner spray.

Posted

I had a similar issue like that I would be leaving the parking lot letting the fast idle pull the truck up to speed then add alittle light throttle then it would surge off and on some. Went to a aftermarket throttle body and haven't notice it since.

  • 4 years later...
Posted

Did anyone ever figure out what this was caused by? I have a 2015 GMC Sierra with the 5.3 doing the same thing today. 10 degrees outside. Only does it while cruising down the interstate. No codes stored or engine light. 

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