Shopping for new truck and have question.

Gary Doolin · June 3

Ok guys im sure this has been discussed and have did a search and read some answers. Im looking to buy a 2500 gmc. The highest trim level i will buy is more than likely the SLT and more than likely will buy the SLE. My question is should I buy an older model with the 6l90 or buy new with the 10 speed. Im in Southeastern Kentucky. So it's a mix of terain. My local dealership offers lifetime power train warranty on anything except diesel and anything 8 years old and newer. The total towing weight I will be pulling regularly (2-3x times a mouth) would be around 10k. If that makes a difference other than that it will be my daily driver. Im totally new to the 3/4 ton truck and either trans. I still have a 06 with 4l60e so any help will be very much appreciated.

Thank Gary

No F-bdy Bs · June 3

I think you'll be happier with the 10spd. Real world issues are actually pretty rare dispite the hype Nate puts out.

Gary Doolin · June 5

On 6/3/2026 at 11:02 AM, No F-bdy Bs said:

I think you'll be happier with the 10spd. Real world issues are actually pretty rare dispite the hype Nate puts out.

Thanks for the reply. Im not sure what you mean by the hype Nate puts out. I dont really know much about either trans. I do hear more about the 10 speed transmission having issues but im sure it's only a small % of them that are manufactured. I have heard that the 10 keeps you in the power curve more with less Rpm drop. My stepfather has a 10 speed in his 1/2 ton and im not crazy about the way it shifts and he has started experiencing shudder at 100k.

No F-bdy Bs · June 5

7 hours ago, Gary Doolin said:

Thanks for the reply. Im not sure what you mean by the hype Nate puts out. I dont really know much about either trans. I do hear more about the 10 speed transmission having issues but im sure it's only a small % of them that are manufactured. I have heard that the 10 keeps you in the power curve more with less Rpm drop. My stepfather has a 10 speed in his 1/2 ton and im not crazy about the way it shifts and he has started experiencing shudder at 100k.

A lot of people also forget the old 6spd was pretty good at the torque converter snout wearing into the front of the trans case. Pretty common issue. 6spd was not a perfect trans by any means.

stlchevy61 · June 5

Go for the 10-spd. I have a 2024 3/4 ton and 1 ton dually. We are now at over 100k miles between the two. The 3/4 ton doesn't tow as much and I have had zero issues. The 1 ton tows a couple times a week, 10-16k depending on the machine I am moving. Both trucks are used for construction and also spend time at the farm, have been great. Had an issue with the 1 ton and GM replaced the valve body in the transmission, it was down for 3 weeks which sucked, but it was all covered. It tows great and I really like the 6.6 L8T. Maintenance has been easy, I do all oil and fluid changes myself. The front end is greasible, so make sure you keep everything lubed up.

On our 2018 3/4 ton with the 6.0 I just had to use our unlimited powertrain warranty. I thought the warranty would never actually pay, but once they saw the engine was spotless inside at 180k and the only issue was a failed camshaft bearing, they paid 12k for a new engine. Always thought those warranties were a scam, but if you are diligent about maintenance and keep track of your records, they are great. Many of the oil changes were self performed, but I had all the receipts from buying the oil and filters, and had a log with the mileage I changed it at.

BuckWallace · June 5

I have about 27k on my 2024 with the L8T and 10sp and haven't had any issues so far.

Another JR · June 6

The 6L90 in the 2020+ trucks has several improvements over the 6L90 in other trucks, so the comments made about issues with previous versions may not apply. I have been totally happy with the 6L90 in my 2021 3500 HD. The L8T has plenty of torque over a wide speed range and does not need to be held in a narrow rpm range unless you are towing near the maximum weight. Even then, six gears works just fine. Personally I don’t like what i consider the excessive shifting of most ten speeds, but i have not towed with one of these trucks with a ten speed. If you are buying used I would prioritize condition, miles, maintenance records, absence of stupid unreversible modifications, and towing history as more important than ten speed versus six speed.

Make sure you try the seats out before choosing a trim level. I can drive my SLT with the leather bucket seat (premium pkg) option for 8 hours and get out feeling fine. I was uncomfortable in the SLE cloth seats with fold down center seat by the end of a 20 minute test drive. My wife loves the SLT leather bucket seats, too.

c4racer2 · June 9

I wouldn't buy a 5 year old truck just because of the 6 speed vs. 10 speed. You really have no idea how it was treated and the motors surely have improved over time so I figure the newer the better - get a new or 1-2 year old truck with very low miles - I really prefer to buy new vs. a year or two old too so you can really know exactly how it has been treated and maintained - I think the first 25K miles are pretty critical in the long term reliability of these trucks.

KARNUT · June 9

12 minutes ago, c4racer2 said:

I wouldn't buy a 5 year old truck just because of the 6 speed vs. 10 speed. You really have no idea how it was treated and the motors surely have improved over time so I figure the newer the better - get a new or 1-2 year old truck with very low miles - I really prefer to buy new vs. a year or two old too so you can really know exactly how it has been treated and maintained - I think the first 25K miles are pretty critical in the long term reliability of these trucks.

That’s exactly how I felt. What’s changed? Information. You can track 5 year old vehicles. You have carfax and the internet to get information on how vehicles are holding up. The discounts for older vehicles with depreciation is hard to pass up. It only took me 50 years to change my ways. The money Ive saved is in the six figures. Of course my driving is less now. I have to write this down as a reminder to myself as the new vehicle bug is always biting. At least buying older vehicles I’m getting better return on vehicles. And I have more to drive.

GAMark · June 9

I have a 2026 SLE with most of the options, and it tows great.

PunchT37 · June 9

1 hour ago, KARNUT said:

That’s exactly how I felt. What’s changed? Information. You can track 5 year old vehicles. You have carfax and the internet to get information on how vehicles are holding up. The discounts for older vehicles with depreciation is hard to pass up. It only took me 50 years to change my ways. The money Ive saved is in the six figures. Of course my driving is less now. I have to write this down as a reminder to myself as the new vehicle bug is always biting. At least buying older vehicles I’m getting better return on vehicles. And I have more to drive.

Unless you`re running a carfax on mine.

It won`t even show my 1`st free oil change.

KARNUT · June 9

14 minutes ago, PunchT37 said:

Unless you`re running a carfax on mine.

It won`t even show my 1`st free oil change.

Then I wouldn’t be interested in buying it. Unless I knew you personally. That’s kinda of the point.

PunchT37 · June 9

7 minutes ago, KARNUT said:

Then I wouldn’t be interested in buying it. Unless I knew you personally. That’s kinda of the point.

Gotcha. But, as a mechanic, I don`t want anyone touching my stuff. Even under warranty. I have a `25 Silverado, a 2000 Silverado and a `71 Pontiac. All run great.

But, you are correct. One would have to see these things.

KARNUT · June 9

13 minutes ago, PunchT37 said:

Gotcha. But, as a mechanic, I don`t want anyone touching my stuff. Even under warranty. I have a `25 Silverado, a 2000 Silverado and a `71 Pontiac. All run great.

But, you are correct. One would have to see these things.

I’ve gotten lazy in my old age. But I have trusted service technicians I trust.

PunchT37 · June 9

7 minutes ago, KARNUT said:

I’ve gotten lazy in my old age. But I have trusted service technicians I trust.

Double trust, huh?

I hear ya.

Side note, one can get trust off the internet. I belong to a Pontiac message board such as this. I sold a complete running Pontiac 455 that I built in the late `80`s. Most won`t touch a complete engine. Especially an older one. The dude offered me $500 more than I was asking. He paid the truck freight to Lubbock TX. All I did was build a crate for it.

I told the dude he was ballsy. He says, "I trust you".