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8 speed garbage

jrhoyt84

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DAY11 Enthusiast

DAY11

Posted
Posted

So after the latest update with a small change but not a complete correction I went back in. The tech did a fast relearn with a prescribed driving routine. I am happy to say it appears to have fixed my 1-2 shift and harsh downshift.

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seamus2154 Enthusiast

seamus2154

Posted
Posted

I agree with ya buddy. Except for your '15 is a second year K2XX. I was all into C4 vettes years ago. I had an 89, it was great. The cross fire 84 was trash. Then the iron head TPI came out. Then aluminum roller L98, and the 700R4 was not really "good" until '88 IIRC. Yeah.... by the time it's perfected GM stops making it. My father inlaw and I have the same conversation. Does not take a Von brougham to figure it out.. Ford is kinda the same way. I had the last year 6.0 F250. Awesome truck. By then all the bugs were worked out!!

 

84 was the absolute worst C4 made! LOL I had an '85, 1st yr for tuned port, and a '91 with no issues very cool car in that day. My '15 is a Yukon XL Denali first year for this truck. Had the '14 Silverado, the '15 Sierra then gave up on the 5.3 and traded to this for the 6.2 which I love, but find myself routinely at the dealer since I bought it!!! Yep, last two years of any model are the best with GM!!

 

BTW there is a guy on youtube that says that last year 6.0 diesel is the all time best truck ever. Has stats to prove it. Look him up something about dealer proof your truck, he's in Ga.

FL335i Enthusiast

FL335i

Posted
Posted

I've seen that guy... he runs a diesel shop in GA. It's funny stumbling upon this stuff 10yrs later. I remember when i bought my '07 6.0, there was only 2 left on the lot, all the '08's where on-site. My buddies ragged me so bad.... 6.0 sucks bla bla. I did my research and knew that ford had made changes to the EGR system in '05 or '06. Aside from the truck being the size of a house, c-channel frame that flexed a lot of off-road and the noisy diesel engine... loved that truck. Huge interior, transmission was great, straight axles etc. But for my usage the new 1/2 tons tow what I need. in '07 the 1/2 ton tow ratings were a lot lower than today's.

seamus2154 Enthusiast

seamus2154

Posted
Posted

We all want the latest and greatest. I have learned over the years newer is not always better.

 

My 07 Sierra 5.3 LS1 was in the dealer once in 6 years, flawless. These last three trucks in this platform are regularly at the dealer. ridiculous.

sdeeter19555 Senior Enthusiast

sdeeter19555

Posted
Posted

I keep seeing this thread at the top of my feed and find it odd GM has such issues with their 8spd.

 

My dad has a 2013 Ram 1500 with the hot 5.7 hemi of that time and the 8spd...in the limited time I've been riding around with him, I've never noticed a weird shift or anything odd...it shifts when it should, no clunking, most times you can't even feel it shift. And he runs the pants off that thing for an old man...

 

Why can Dodge seemingly get it right and GM flounder around with it? Makes no sense to me.

 

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gilleydog Enthusiast

gilleydog

Posted
Posted

time to trade for a dodge ? always been a chevy man

Lalibert Enthusiast

Lalibert

Posted
Posted

I am in the same boat here I have at 17' that I bought in December, I have close to 14,000 miles on it along with 3 trips to the dealership. 1st time the dealer did the relearning and that made it better but after 3-4000 miles it got worse. 2nd trip to the dealer and "transmission tech" rode with me and got the " o that is normal" when it was clunking and jerking in and out of 1st and 2nd. I told him that $50,000 truck shouldn't do that, he went on to say it was because the trans gets some "slack" in it and that it why it clunks.

Left the dealership frustrated figured I would live with it but another month went by and I couldn't deal with it so had the Service Manager ride with me and of course I couldn't get it to do it so now after a 300 mile road trip it is back to it's old ways of being garbage so I guess I will be doing another ride along with the Service Manager soon.

 

 

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ajanes89 Enthusiast

ajanes89

Posted
Posted

Dodge has these problems as well, like gm not ALL trucks suffer from this headache. I just got my 15 6.2 8speed back for a SLIGHT vibration at 73+. The shifting was also sloppy but didnt bother me much. They road forced balanced the tires and did a update on the ecm and tcm. Just finished driving to northern maine from Ct and i can honestly say its a completely different truck. Shifts flawless, holds gears longer on hills, and smooth as silk. Like i said before its all in the tune. Call up lew or black bear if your not having any luck with your dealer. Ill be calling lew soon also to fully wake her up..

 

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MS3DALE Senior Enthusiast

MS3DALE

Posted
Posted

So GM and Ford co-build a 10spd transmission. The F150 gets the 10spd and GM is using this 8spd. Wondering why doesn't GM also have the 10spd? Is the 8spd an interim transmission and the 10spd will be in the '19's? My only complaint about my 6spd is in heavy city traffic it's a bit lethargic, aside from that it's great. The fix for city traffic is I put it in M4 or M5. I'll be honest, the 8spd is one reason I'm plenty happy waiting out for a new truck.

 

GM is using the 10-spd in the new Camaro ZL1

MS3DALE Senior Enthusiast

MS3DALE

Posted
Posted

BTW....I'll add,no issues with my 8-spd, but I only have 7k on it and I do have a Black Bear tune, so far I love it.

ajanes89 Enthusiast

ajanes89

Posted
Posted

I also averaged over 21.5 mpg and touched 23.5mpg, with about 1000k of gear and people. 10speed also going into tahoe rt.

 

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  • 1 month later...
mikepol2 Enthusiast

mikepol2

Posted
Posted

BTW....I'll add,no issues with my 8-spd, but I only have 7k on it and I do have a Black Bear tune, so far I love it.

Can you give us any more details on the results from your BB tune? I have a 2015 6.2 with the 8-speed and 33K miles but am leery about tuning because I don't want to jeapordize the 6 yr/100,000 mile powertrain warranty that came with the 15's.

Skidsareforkids Enthusiast

Skidsareforkids

Posted
Posted

I've got 12,000 on my '17 6.2 8sp and it's starting to get irritating. The usual, clunk in reverse and hard downshifting at low speeds, it has "pushed" a couple of times coming to a stop too [emoji19]

My wife's '16 Denali XL has the same setup, but even at 67,000 it hasn't missed a beat, so I just can't believe how it can be so different with the Sierra [emoji849]

 

 

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Sir Dan Enthusiast

Sir Dan

Posted
Posted

Denali is built in Arlington Tx and the Sierra comes from Fort Wayne, IN. Maybe TX plant used a better tune for the SUVs or a better fluid. I've heard some people getting a fluid flush and change get better shifting.

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