Shudder/Vibration Issue

ForumUser · January 25, 2019

Service manager called back ...

He outlined what he had been told, then shifted to his experience driving loaner Silverados ... that his wife had asked him on way home one night ...”what is that? What’s wrong with it? “. He told her “nothing, they all do it,” then explained he needed to have the trans fluid flushed.

I was kind and noted ,a agin, my experience with it and my online findings ...

He agreed, even though they couldn’t replicate the issue on mine, that there was enough evidence for them to change the fluid, as long as I knew it might not resolve it.

He then related story of a guy who had issues in 2018 for months and he finally authorized his guys to change the fluid in mid December, after they had received the fluid but had not been authorized to change it by GM .... has not heard back from the guy.

we’ll see

pddug69 · January 25, 2019

FYI, went to local dealership and explained to the service manager this issue and he immediately confirmed that the fix is flushing the transmission fluid and replacing it with a different type of fluid (not sure about all the specs). Am having this done Monday morning and will report the results some time next week. BTW, also getting nitto ridge grapplers 305/55r20 installed, truck has rough country 2 inch level up front.

Also noted that the issue really wasn't present until the transmission fluid was at least 88 degrees or warmer.

Edited January 25, 2019 by pddug69

ForumUser · January 25, 2019

pddug,

88 degrees C for the fluid, right?

pddug69 · January 25, 2019

have mine set of fahrenheit

ForumUser · January 25, 2019

I may be duplicating my post - but, I can't find the post I saved so will do this again ...

They flushed and swapped fluids per the procedure shown on the attached photo ...

On 10 mile drive home seemed like a normal transmission ... no shuddering, no jerking ... didn't even clunk at intersections while slowing for the light.

Will see ...

ForumUser · January 25, 2019

pddug,

Transmission fluid would heat up pretty quickly - 88F is really cool - not even skin temperature ... you sure?

ForumUser · January 26, 2019

Here’s the new stuff ...https://www.mobil.com/English-US/Passenger-Vehicle-Lube/pds/GLXXMobil-1-Sythetic-LV-ATF-HP?p=1

pddug69 · January 26, 2019

Appreciate the info. Am sure about the temp in fahrenheit, it was a cold night and the temp got to 117 deg F at it's hottest.

ForumUser · January 26, 2019

brrrr ... that is a cold night .... been reading on it ... pretty common to stay way lower temp since temp isn’t controlled like on the engine and there is no combustion sou CS driving it.

As a BTW, both service reps at my dealer said they read in their GM info sheet that the shudder was more common in hot climates. I don’t have any data at all on this point.

ForumUser · January 27, 2019

Put about 240 miles on the new fluid today .... noticeably less clunk upshifting from 1-2 under light throttle, and downshifting while easing up to traffic lights.

Rock solid rpm while cruising at 1200-1500 rpm ... no waver, no rumble strip feel and no weirdness as it upshifted with light throttle at higher speeds ... smooth downshifts while slowing from higher speeds.

Need more time, but seems much, much improved.

bigman32hockey · January 27, 2019

Has anyone on here ever tried the Lube Gard Dr. Tranny Instant Shudder Fix? I know it's not a permanent fix, but from the reviews I've read the stuff seems to actually work. I am only looking for a temporary fix until my dealership receives the new tooling from GM. This is supposed to be sometime in mid-February 2019. I can't stand driving the truck around with it shuddering like it does. It's just too annoying. My only concern is if I add this stuff, I obviously don'y want it to do more harm than good. I'm not sure if it will affect seals, etc.. It's all going to be flushed in a few weeks, but I want to make sure it won't affect GM's procedure to permanently fix the shudder issue. Thoughts?

ForumUser · January 27, 2019

Big man,

The fluid looks to be pretty widely available - https://www.thelubricantstore.com/mobil-1-synthetic-lv-atf-hp-case-6-quarts?gclid=EAIaIQobChMImIeL5YyO4AIV6iCtBh0DngmtEAQYASABEgL7SvD_BwE

Your dealer should have access to it now.

i would not add anything that would void the warranty.

pddug69 · January 30, 2019

Had the transmission fluid replaced 2 days ago. So far the shudder issue is corrected. Time will tell, thanks everyone for the info.

G3108 · February 1, 2019

What is the status on most recent tranny flush ? 2018 6.2 with 8speed

G3108 · February 2, 2019

On 1/30/2019 at 5:18 PM, pddug69 said:

Had the transmission fluid replaced 2 days ago. So far the shudder issue is corrected. Time will tell, thanks everyone for the info.

How is tranny doing..