Truck jerks when braking in 4 low

Forrest_E · April 30, 2020

I went to the beach this past weekend and put it in 4 low due to the deep sand. Every single time I would brake to stop the truck would lunge forward and jerk back before coming to a complete stop. It does not do this when I am in 2wd or 4 high. Is this a transmission issue or a programming issue that can be easily fixed? It's a 2020 LT Trailboss. I had a 2019 prior and this never happened.

BlancoSilverado · April 30, 2020

Have you tried doing it on asphalt?

Forrest_E · April 30, 2020

30 minutes ago, BlancoSilverado said:

Have you tried doing it on asphalt?

I did a couple of days later and it still lunged forward and jerked back before coming to a complete stop.

Silverado4x4 · April 30, 2020

7 hours ago, Forrest_E said:

I went to the beach this past weekend and put it in 4 low due to the deep sand. Every single time I would brake to stop the truck would lunge forward and jerk back before coming to a complete stop. It does not do this when I am in 2wd or 4 high. Is this a transmission issue or a programming issue that can be easily fixed? It's a 2020 LT Trailboss. I had a 2019 prior and this never happened.

Every 4wd truck I have owned did this in 4L, its the truck shifting from 2nd gear to 1st gear when coming to a stop. The drivetrain is very touchy in 4L due to the very low gearing.

MORGENSHTERN · May 1, 2020

My vehicle sat for a few months due to the fact that I lost my driver's license. I still had a friend drive it around town now and again to give the battery some juice. We never noticed braking issues. But now that I have my license back and I'm driving it daily, I'm noticing an inconsistency in the way the brakes work. Instead of smoothly stopping, it's a choppy, uneven stop. I have been told that the brake pads/components may have rusted while sitting and it may take some time to even out again. However, I've been driving for 2-3 weeks, I've put on 30-50 miles and the brakes are still inconsistent. Do I need new pads? Do I need to take it out on the highway and go for a "real" drive to truly knock the rust off? Is this an issue I can remedy myself without taking it to a mechanic shop?

Forrest_E · May 1, 2020

13 hours ago, Silverado4x4 said:

Every 4wd truck I have owned did this in 4L, its the truck shifting from 2nd gear to 1st gear when coming to a stop. The drivetrain is very touchy in 4L due to the very low gearing.

They have all gone forward nearly a foot just before a complete stop then jerk back at least 6"? I have never been in a 4wd vehicle that has done this nor do I see anyone else trucks lunge forward and back when stopping on the beach... It's not just a little jerk, and I don't think any car manufacturer wants to give the occupants whiplash in 4 low. My 2019 LT Trailboss didn't do this, that one just had repeat brake failures to the point I was going to lemon it until they agreed to buy it back in full without the hassle .