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Who likes their 8 Speed?

JacobC1983
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JacobC1983
JacobC1983

I care about warranty.... It pays for repairs that otherwise I would have to pay for out of pocket. Actually, lots of people care about warranty on a $50k+ vehicle.

mitchellb2005
mitchellb2005

I love my 8 speed. I never hate it, but sometimes it does small annoying things, but I expected an 8 speed to be a little finicky sometimes since I also have an 8 speed in my Audi A7. Once you learn w

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wildlyfe200 Enthusiast

wildlyfe200

Posted
Posted

I've got the 6.2/8 spd and get the hard down/up shift every now and then, invariably when coming slowly to a stop or taking off from a stop kinda slowly. It seems it's a gear searching problem between 1st and 2nd gears, premature shifting both up and down. With the 6.2 420hp/460ft lb engine I fail to see the need to utilize 1st gear when driving in a no-load situation. I've owned trucks with manual transmissions in the past and when just dogging along I would rarely start off in what was referred back in the day as compound or granny gear. Was just a waste of time. Sooo, my suggestion is for GM to program their 8 spd (and upcoming 10 spd) to block out 1st gear unless the tranny senses a load or is in tow mode. How hard could that be?

Your exactly right. The only time i get a bad clunk is when i am slowing down to a stop at a low speed. It down shifts into first and clunk. I did get a full tune helped a bit. It keeps in the gears higher up in the RPMs. Also downshifts a little sooner where i get some engine breaking going on. Now I get a slight lurch forward when down shifting into first instead of a clunk. I'll take that over the clunk.

 

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wildlyfe200 Enthusiast

wildlyfe200

Posted
Posted

when is blackbear in town to do a tune? any other companies that tune the 8-speeds?

If you got a 2017 8 speed Blackbear cant help you. They use EFI Live only I had to go to a shop that uses HPTuners and it still has a few caveats to get it all tuned.

 

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  • 4 weeks later...
Snoringbear Enthusiast

Snoringbear

Posted
Posted

Well.....

being things are going so well with the 2017's; maybe the header should be changed to "Who Likes Their 10 Speed?" Believe it's scheduled to show in the 2018 HighCountry, Denali, LTZ, SLT .

wildlyfe200 Enthusiast

wildlyfe200

Posted
Posted (edited)

Well.....

being things are going so well with the 2017's; maybe the header should be changed to "Who Likes Their 10 Speed?" Believe it's scheduled to show in the 2018 HighCountry, Denali, LTZ, SLT .

I got some gripes with my 2017 8 speed the clunking is really annoying. Tune helped but its still there. I can deal with it but everytime it happens can't help but feel like it's damaging something inside the trans. Luckily it only happens once or twice a week i drive on average 80-90 miles a day.

 

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Edited by wildlyfe200
Snoringbear Enthusiast

Snoringbear

Posted
Posted

I got some gripes with my 2017 8 speed the clunking is really annoying. Tune helped but its still there. I can deal with it but everytime it happens can't help but feel like it's damaging something inside the trans. Luckily it only happens once or twice a week i drive on average 80-90 miles a day.

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Yup, I've had three tunes, helped a little for a short while I think, although it could be my imagination. As I've posted upstream, I have the same clunking problem same as many others. Even the Truck Trend guys doing their long term testing of a 2015 Denali have complained about it. Personally, I think the problem is with the 1st > 2nd and 2nd > 1st gear shift points. I've noticed that the way I drive has a lot with the clunk happening. I'm old and retired, so much of the time I'm in no hurry to get from one place to another. Sooo, when I make one of those slow rolling stops through a neighborhood stop sign the tranny tends to downshift into 1st prematurely and conversely when I take off from a dead stop kinda leisurely it upshifts prematurely. Gives my old neck a snap kinda like I've been rear-ended. But, as another poster has stated, if I "drive it like I stole it" the tranny seems to shift through the gears pretty good. And, it shifts ok when pulling my 6,000 lb camper as well. Which is why I continue to put up with it :)

wildlyfe200 Enthusiast

wildlyfe200

Posted
Posted

Yup, I've had three tunes, helped a little for a short while I think, although it could be my imagination. As I've posted upstream, I have the same clunking problem same as many others. Even the Truck Trend guys doing their long term testing of a 2015 Denali have complained about it. Personally, I think the problem is with the 1st > 2nd and 2nd > 1st gear shift points. I've noticed that the way I drive has a lot with the clunk happening. I'm old and retired, so much of the time I'm in no hurry to get from one place to another. Sooo, when I make one of those slow rolling stops through a neighborhood stop sign the tranny tends to downshift into 1st prematurely and conversely when I take off from a dead stop kinda leisurely it upshifts prematurely. Gives my old neck a snap kinda like I've been rear-ended. But, as another poster has stated, if I "drive it like I stole it" the tranny seems to shift through the gears pretty good. And, it shifts ok when pulling my 6,000 lb camper as well. Which is why I continue to put up with it :)

I have the exact same experience as you. If im coasting along and slowing to a stop thats how it happens 90% of the time. Once in a blue moon taking off slowly. It is between 1st and 2nd for sure. I think the tune seems to help a bit because they made it downshift sooner but between the trans. Relearn after a flash and all of that who knows. Its sucks but not a huge deal becuse it doesnt happen often.

 

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Snoringbear Enthusiast

Snoringbear

Posted
Posted

Personally, I think the solution would be for GM to program the 8 spd so that it would not utilize 1st gear in no-load or light-load situations. When doing routine driving and not towing or hauling the 8spd bolted up with the 6.2L 420 hp/460 ft lb engine is more than capable to take off from a dead stop without using 1st gear. However, so to accommodate those that may want their 1st gear activated all the time all the would have to do is push the tow button and they would have it. Seems an easy fix to me.....

wildlyfe200 Enthusiast

wildlyfe200

Posted
Posted

Personally, I think the solution would be for GM to program the 8 spd so that it would not utilize 1st gear in no-load or light-load situations. When doing routine driving and not towing or hauling the 8spd bolted up with the 6.2L 420 hp/460 ft lb engine is more than capable to take off from a dead stop without using 1st gear. However, so to accommodate those that may want their 1st gear activated all the time all the would have to do is push the tow button and they would have it. Seems an easy fix to me.....

I have a feeling that that's what they are going to do with the 10 speeds. I would be curious to see the gear ratio chart with the 10-speed compared to the 8-speed.

 

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seamus2154 Enthusiast

seamus2154

Posted
Posted

Personally, I think the solution would be for GM to program the 8 spd so that it would not utilize 1st gear in no-load or light-load situations. When doing routine driving and not towing or hauling the 8spd bolted up with the 6.2L 420 hp/460 ft lb engine is more than capable to take off from a dead stop without using 1st gear. However, so to accommodate those that may want their 1st gear activated all the time all the would have to do is push the tow button and they would have it. Seems an easy fix to me.....

 

This is exactly what Mercedes does on the 7 speed in the S550. Pulls from a stop in second gear. Now if you put it in sport mode it starts in 1st gear. But all normal driving even very slow it doesnt drop to 1st unless you floor it. And it's smooth and always in the right gear, so GM could do it as it is just in the tuning. The just wont do it! Now I fear they are abandoning the 8 speed which I like for alot of other reasons, especially towing. The 2018 Denali is getting the 10 speed.

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