5.3L stutter at 1,500 rpm

[Danno3170]

I have a 2021 Trail Boss LT, 5.3L. The truck has a noticeable stutter between 1,200 and 1,500 rpm. The longer it is driven, the more noticeable it is especially at higher speeds. The truck as 56,000 miles with a K & N air filter. Any thoughts?

 

[mrcolieman]

Hard to diagnose over the interwebs but could be the "shudder" from torque converter clutch slippage. Check for issues with a scan tool to be sure. If that is the problem then service the trans, replacing filter and using high quality synthetic fluid. if you live in a warm climate you may want to install a transmission thermostat bypass as well. If there is metal in the trans pan then you will probably want to replace the torque converter before it wipes out the transmission with debris from continued failure.

 

[Danno3170]

The absence of a check engine light would seem to imply a transmission issue.
Many thanks for the reply. I’ll take a look at it today.
Dan

 

[Midnight TB]

Lots of reasons that could be the cause. AFM/DFM engaging/disengaging, trans valvebody issue, engine misfire (bad gas? maybe try fresh 93 octane in case of spark knock), bad torque converter. K&N air filters have been known to throw some oil on MAF sensors and cause some drivability issues but believe these trucks are speed density system and no MAF. Happy hunting!

 

[Danno3170]

Thank you!

 

[Stormin08]

If it is doing at that low of RPM, most likely your are accelerating from a stop or loading the engine in lower rpm...sound about right ????

I am going to put my money on torque convertor based on your description....when it fails or as it is failing, the slippage is sending debris through out the trans and you will be rebuilding it as well.

 

[Danno3170]

If it is doing at that low of RPM, most likely your are accelerating from a stop or loading the engine in lower rpm...sound about right ????

I am going to put my money on torque convertor based on your description....when it fails or as it is failing, the slippage is sending debris through out the trans and you will be rebuilding it as well.

It isn’t present during acceleration from a stop. Rather, driving down the road. It is most noticeable on the highway with soft throttle acceleration.

 

[Danno3170]

I have eliminated the fuel management system, plugs, and fuel. I ordered a new MAF sensor.

 

[Stormin08]

It isn’t present during acceleration from a stop. Rather, driving down the road. It is most noticeable on the highway with soft throttle acceleration.

very common sign of torque convertor, we have 1K plus services trucks on the road, they have all started with what would be similar to a rumble strip...steady or light throttle input, mild load and it starts to shutter. could last a lifetime, could last 1 more time...

 

[Danno3170]

Ok, good to know. Thanks for the reply!