Who likes their 8 Speed?

Bohnman · September 17, 2018

Not yet I'm dropping it off tomorrow.

L86 All Terrain · September 17, 2018

I had the delayed shift to reverse start about a month ago. Took it in for the delayed shift bulletin and provided number, TSB calls for a new stator shaft in the trans, after 1 week they informed me that they wanted to put a new trans in. A reman 8L90e was installed and I finally have the truck back after 3 weeks. Took it to the city to drop some stuff off for my business to test it and it shifts awesome, even better than my old one which was fine minus the delayed reverse. GM said the reverse clutch packs were toast for the one week that it occurred. To top it all off, someone decided to run into me at the fuel pumps in the city with a sailboat and totalled my front bumper. $2,650 all in for a new one, courtesy of his insurance. Last time I decide to take my comfy personal rig on a work run. Here is the TSB if any of you have the same issue. http://www.corvetteactioncenter.com/tech/knowledgebase/article/2015-2016-corvette-service-bulletin-16-na-014-delayed-engagement-after-sitting-with-engine-off-1290.html

Hopefully this 8L holds up.

samckitt · September 19, 2018

Has anyone tried this stuff? Colorado/canyon forum members have stated they have had good luck with it.

seamus2154 · September 20, 2018

That was a fix on the BMW forums for the 740I TC issues. Many guys had good success with it. Some said a year later that needed to use it again. Our TC issue as explained to me by a service manager is a manufacture defect. Apparently a batch when made and pressed together rolled over an internal seal which fails. It was later determined and corrected with a new part number so no new old stock would be used for the fix. I had this issue fixed under warranty on my 2015. It worked. If I were in warranty I would not be chasing the fix with shudder fix .

samckitt · September 20, 2018

I will take it back again, but have already had the flush done, & had torque converter replaced. Symptoms have not changed a bit, still shudder & hard downshifts are still there.

Bohnman · September 20, 2018

Got the truck back yesterday they did a fluid flush and a Filter replacement and told me to drive it for 200 miles to see if the shudder goes away. On my way in to work today I didn't feel it one time so my fingers are crossed.

Pearl2017 · September 22, 2018

FWIW ...My fluid flush and filter was a couple months now and still running smoothly. They didn't say anything about applying update/s. In HPTuners I can see that the OS level has been incremented. (They loaded newer OS or patched it). I agree the issue is either defective hardware or that and software tweak. I have user LubeGuard in the past in older vehicles I guess if you've exhausted dealer fixes its worth a try it is a friction modifier so makes sense it could help with chattering TCC.

Bigmac · September 23, 2018

On 9/19/2018 at 7:10 AM, samckitt said:

Has anyone tried this stuff? Colorado/canyon forum members have stated they have had good luck with it.

Wondering how to install since there is no trans dipstick? Worth a try ??. Disconnect trans cooling return line on radiator or cooler I would think. Anybody figure it out?

samckitt · September 23, 2018

I read somewhere that they removed cooler line at radiator and squirted it in the line. There isnt much, 2 ounces.

Edited September 23, 2018 by samckitt

sigmonster · September 24, 2018

An update to my truck. 2017 6.2L NHT Sierra. It started shuddering after 25,000 miles (and a week of towing).

First the dealer changed the fluids and I drove it 200 miles. No change in the shudder.

Last week they changed the torque converter. It was at the dealer 4 days and they listed 21.5 hours of labor on the warranty claim!!

It now is smooth as butter. Still an occasional clunk when cold in a parking lot (another 8 speed issue).

Love my truck again.

L86 All Terrain · September 26, 2018

On ‎2018‎-‎09‎-‎24 at 9:11 AM, sigmonster said:

An update to my truck. 2017 6.2L NHT Sierra. It started shuddering after 25,000 miles (and a week of towing).

First the dealer changed the fluids and I drove it 200 miles. No change in the shudder.

Last week they changed the torque converter. It was at the dealer 4 days and they listed 21.5 hours of labor on the warranty claim!!

It now is smooth as butter. Still an occasional clunk when cold in a parking lot (another 8 speed issue).

Love my truck again.

Hope it works out for you. They changed my TC before I even bought the truck new off the lot. Now that trans took a dump and they through in a Reman trans in a truck with 20,000 miles. Talk about confidence inspiring. I wont be keeping this truck after warranty if I can afford the obscene asking pricing for a 2019+.

thetruck454 · September 27, 2018

I just went to order an updated torque converter (p/n 24285996) and was told the new part number is 24290214. I've Google searched for that updated part number and can't find anything. Anyone have that updated torque converter installed?

samckitt · September 27, 2018

My paperwork says the used torque converter 24286975, 2018 5.3L

samckitt · September 28, 2018

This hard "clunk" feeling, i thought was during shifting gears. This morning, daughter was driving (I take her to school), and backing out of the drive, she gave it gas & let off & got the hard clunk. Reverse only has one gear right, so what is the clunk?

Snoringbear · September 29, 2018

21 hours ago, samckitt said:

This hard "clunk" feeling, i thought was during shifting gears. This morning, daughter was driving (I take her to school), and backing out of the drive, she gave it gas & let off & got the hard clunk. Reverse only has one gear right, so what is the clunk?

A couple of possibilities come to mind, just guessing; could be the driveshaft slip yoke. Had a 2005 that when taking off from a dead stop or backing up would make a loud clunk and sometimes felt like someone pushed me from behind. Did this when brand new, was a TSB on it had two replacements and multiple greasings. Problem was never completely fixed, diminished with time and miles. The other possibility; might be lash in your differential, especially if happening only when you go to reverse. Lastly, could be happening just cause it’s a Chevy. Example; I’ve been driving GM 1975 and have had trucks and Burbs with sticking power mirrors. Never even once had the problem repeated at a dealer, just learned to live with it. Personally, I think there are little nefarious design engineers hidden in a cubicle somewhere that designs stuff like this on purpose. Way back in the day I was cursed with rear main seal leaks. But, think the gremlin who designed these retired or died ?.