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6 speed or 10 speed Allison. Which do you prefer?

Gray

By Gray
in 2020-2026 Silverado HD & Sierra HD

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Gray Enthusiast

Gray

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Posted

I bought a 2019 GMC 3500 Denali 4x4 dually, and now I am second guessing myself if I should have waited for the 2020. I tow a 24’ stock trailer almost everyday and actually only tow at most 14000 lbs. Truck handles nice and is way better than my 2012 Dodge 3500 that I traded in. Are the 2020 going to be that much better?

Thankful Enthusiast

Thankful

Posted
Posted

I've owned several of the 6 speed Allison transmissions since my first  GM Duramax in 2005.  Without a doubt, the 10 speed Allison is much better.

2020 GMC Sierra Denali Duramax (crop).JPG

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J-man67 Senior Enthusiast

J-man67

Posted
Posted
there is always something better next year.  your 2019 is a fantastic truck that will do anything you ask of it.  don’t fall into that trap!
Especially for 14,000lbs. Your truck will handle it just as well. The 10spd is a great trans, but I'd say it's more for getting crazy heavy loads going and keeping them going.

Sent from my SM-N975U using Tapatalk

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Colossus Senior Enthusiast

Colossus

Posted
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Ditto on sticking with the 2019.  Having the newest and latest isn't always the greatest.  In fact 9 times out of ten it isn't. 

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Donstar Senior Enthusiast

Donstar

Posted
Posted
6 hours ago, Gray said:

I bought a 2019 GMC 3500 Denali 4x4 dually, and now I am second guessing myself if I should have waited for the 2020. I tow a 24’ stock trailer almost everyday and actually only tow at most 14000 lbs. Truck handles nice and is way better than my 2012 Dodge 3500 that I traded in. Are the 2020 going to be that much better?

Your truck is outstanding!  You recently purchased the top dog in the GM pickup department and may never utilize its full capabilities.  Enjoy your truck!  

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Gray Enthusiast

Gray

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Thanks for the feedback. Up to 1996 I was a GMC man, switched to a Dodge Dually and loved that truck. At the time I thought the Dodge had a better truck. It was a 6 speed with the 5.9L. Great truck. Still have a 2001 Dodge dually and sons both drive Dodge 1 tons. Then I got a 2012 Dodge Laramie Limited, and although that was a great truck, never felt good about the 68rfe transmission. So I thought I would change to the proven Allison transmission in the GMC. Only have 16000 Kms on truck, but already know it is way smoother at shifting, and being a dually, a lot more stable. Not sure about the independent front end yet, as all my dodges had solid axles, but wow, is it smooth riding! I bought the 2019 as it was the last year of the 6 speed transmission which has been proven reliable. Thought about the 2020, as it has a few upgrades I liked, one being a camera in the bed when you back up trailer, the other being keyless start. Got a great deal on the 2019 and the 2020’s were not out yet. Anyways, I like the truck as I think it is a pretty solid unit in all. My buddies all bug me that I bought a GMC, but hey, I needed to find a reliable transmission as I haul a trailer with cattle in it almost everyday. 

Jglew82 Enthusiast

Jglew82

Posted
Posted

I think yours will give you all that you’re looking for. Stick with the proven platform! Also I was pretty sure the new 10-speed is a GM designed and manufactured unit with Allison branding, while yours is Allison design and mfg. if that makes any difference to you. Time will tell how the new one holds up.

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CRApex Enthusiast

CRApex

Posted
Posted

11,000 miles on my 10spd and so far I prefer it over the 6spd.  Like others have said, time will tell on reliability but so far so good.

RyanbabZ71 Senior Enthusiast

RyanbabZ71

Posted
Posted
I've owned several of the 6 speed Allison transmissions since my first  GM Duramax in 2005.  Without a doubt, the 10 speed Allison is much better.
616698072_2020GMCSierraDenaliDuramax(crop).thumb.JPG.2430ea4f8610f58fe335c5953622e830.JPG


Why do you say this? The 6 speed has been around much longer and is well documented to be very reliable. Not disagreeing with you as I think the 10
Speed will turn out to be very good but we haven’t seen the longevity of the 10 speed yet like that of the 6 speed


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Thankful Enthusiast

Thankful

Posted
Posted
1 minute ago, RyanbabZ71 said:

 


Why do you say this? The 6 speed has been around much longer and is well documented to be very reliable. Not disagreeing with you as I think the 10
Speed will turn out to be very good but we haven’t seen the longevity of the 10 speed yet like that of the 6 speed


Sent from my iPhone using Tapatalk Pro

 

Ryan, better doesn't mean the reliability is the same.  Only time will tell.  Better means the ten speed transmission performs better than the six speed.

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Colossus Senior Enthusiast

Colossus

Posted
Posted

I'd like to give it another 3-4 years to see how the 10 speed holds up.  Here's to hoping.  the 6 Speed has done great since it came out in mid 2007.  They won't handle heavy performance tunes without being built up a bit but long term, they are solid 500,000+ mile trannies if you service them right and don't limp and overheat them. 

i82much Enthusiast

i82much

Posted
Posted

Marginally related, but I bought a 4.3 Silverado back in 2006 because I did not trust those newfangled LS engines and wanted something based on a good old small block architecture.  Looking back, those non-AFM engines of that era are some of the longest-lasting engines of all time!

  • 1 month later...
FP53 New Member

FP53

Posted
Posted
On 12/29/2019 at 4:31 PM, Gray said:

I bought a 2019 GMC 3500 Denali 4x4 dually, and now I am second guessing myself if I should have waited for the 2020. I tow a 24’ stock trailer almost everyday and actually only tow at most 14000 lbs. Truck handles nice and is way better than my 2012 Dodge 3500 that I traded in. Are the 2020 going to be that much better?

Well good question. Towing our camper the 6 speed never downshifted. The 10 speed shifts downshifts quite a bit. The 10 speed is much smoother. I prefer the 6 for towing and the 10 for smoothness.

  • 2 years later...
Wish i had my LBZ New Member

Wish i had my LBZ

Posted
Posted

How do I get paid to lie and say the 10 speed out performs the 6 speed? 
Facts, if you pull a big camper or loads 15000lb or better you will be disappointed with the stock Ford copied 10 speed if you had a real Allison 6 speed.

Fact, you will blow through the converter on any grade. 
Fact the lockup doesn’t work effectively to use the torque of the l5p. 
Fact, you will feel like you are pulling with a mid 90’s gasser downshifting and popping off the rev limiter. 

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