GM 6.2L 420hp and 10-speed

[jfortenbery]

I'm curious if anyone is towing with the Silverado or Sierra 1500 with the 6.2/10-speed. I've got one on order to replace my 5.3L/6-speed. I'm hoping for a slight improvement over my last combo.

Thanks,
Jeff

[Grit_dog]

Draggin up the dead threads here!  Boy howdy….

Just fir kicks on the same topic, anyone considering a late model 1500 Silvy or Sierra for personal and or towing use would be well served to look VERY hard at the 3.0 Diesel. 
It pulls somewhere between the 5.3 and 6.2 overall for power and blows the doors off of both of them for fuel mileage. Even the 5.3 which does real good on gas running bobtail. 
Plus it’s the only new 1/2 ton diesel out there anymore and they are very reliable after the 1st 2nd year models. And even those ain’t bad. 
‘23/24 models also got a nice little power bump makin 300/500 in stock trim and yielding an honest 23-24mpg avg even driving them like a rental!  If ya drive like a grampa they avg high 20s in combined driving and crack 30mpg on flat highway. 

[Fuzz87]

I have a 22 Silverado Z71 With 6.2 10speed 323 gears. We towed a camper (aprox 5000lbs loaded) from upstate New York to Murrells Inlet and back. The truck handled it with ease. Climbing the hills in Penn. and Va. it rarely went over 3200RPM. It handled it so well we are considering getting a bigger camper or beefing up the suspension and getting a 1/2 ton 5th wheel something in the 8000 lb range. Thats why I'm here 

[d1h]

Here is what a 6.2 can do.

[BurbMan]

dakonthemountain wrote:
The magnetic suspension adjusts (supposedly) 1,000 times a second and it's like driving a luxury car, with or without the trailer.

I had that suspension on the Suburban and you're right, it's the best! Only issue is that the shocks cost $150 each when they need to be replaced at 100k miles.

[APT]

GM is similar. USe shifter to pick "Manual" mode. From a stop, it will show '1'. Then use +/- to pick the top gear the transmission will use.

[jfortenbery]

Thanks, CavemanCharlie!

[CavemanCharlie]

jfortenbery wrote:
Thanks for the encouraging responses. I have a question, though. How do you "lock out" specific gears?

On my F-150 there is a button on the shifter stock with a plus and a minus on it. After putting the truck in gear you can push the minus button and each time you do it will lock out a gear. So if you have a 8 speed and you push it once and the tuck will only use 7 gears. Lights on the dash will turn on to tell you.

[jfortenbery]

Thanks for the encouraging responses. I have a question, though. How do you "lock out" specific gears?

[dakonthemountai]

I'll pipe in! My numbers here are general as I don't have my files with me, but it gives you an idea of just what a "half ton" is capable of with the proper equipment. Yes, it was pricey, but I dreamed of a truck like this my entire life, so I was ready for the price with ALL the bells and whistles! As a point of reference, I've been RVing since 1987, with fiftwheels, travel trailers, campers, duallys, etc., and full timed for 9 years in a 30' pull trailer with a single axle one ton truck and then a 36' full wall slider fiver with a GMC extended cab dually.
I purchased my 2018 Sierra Denali, with the Denali Extreme package new in March 0f 2018.It has a 6.2V8 8/4 with 8 speed auto transmission. Empty I average 21.5 MPG. Fully loaded with full tanks and gear, towing, 13MPG. I pull an EVO T2050, dual slide 23' travel trailer (25'11" bumper to hitch) with a max weight of 7,900lbs. I have weighed the rig but I don't remember the exact weight, but it's under the mfg. rating and quite a bit below the trucks tow capacity. The tow rating of my truck is over 9,000 lbs with the extreme package and I can tell you after over 15,000 miles of pulling it I LOVE it! I have never had a truck that so effortlessly pulled a trailer without being a dually (and I've had a number of them!) Never had an issue with power. The magnetic suspension adjusts (supposedly) 1,000 times a second and it's like driving a luxury car, with or without the trailer. Like I wrote, I don't have my paperwork or files with me, but suffice it to say I am Completely happy with it!.... though it WAS more expensive than my first house!
So there you have it. It's not the 10 speed, but I can only say that if it's anything like my 8 speed with the 6.2 you would LOVE it!
Best of luck !
Dak

[jfortenbery]

The data tells me it'll be a decent improvement, but data don't always tell the whole story. What I never liked about my 5.3/6speed was mainly the transmission. On long hills (or should i say slight upgrades), it would shift (in tow mode) from 6th (2,300 rpm) straight to 4th gear (3,800 rpm) skipping 5th altogether. AND, a GM V-8 just don't sound happy to me at 3,800 rpm. This was a Silverado w/ max towing pkg and 3.42 gearing.

BTW, I'm pulling a 32ft Outback 280KRS at about 8,000 lbs. I hope this new combo (and 460 ft/lb torque) will ease on down the road - or up the hills - a bit easier.

[Grit_dog]

3800 rpms is child’s play for any LS motor.
He!! They don’t make real power until 4000 anyways.

I too have a lot of 4000-5000 rpm hours on LS powered trucks. Not an issue.

[APT]

jfortenbery wrote:
On long hills (or should i say slight upgrades), it would shift (in tow mode) from 6th (2,300 rpm) straight to 4th gear (3,800 rpm) skipping 5th altogether. AND, a GM V-8 just don't sound happy to me at 3,800 rpm. This was a Silverado w/ max towing pkg and 3.42 gearing.

2300rpm sounds like 5th gear to me. That 5.3L can sing all day long at 3800rpm for 300k miles. 🙂 I have same trans, 3.73 gears though. 5th gear for me is about 2200-2500rpm at 65-72mph. One gear downshift is 2900-3300rpm. So I think your trans is going 5th to 3rd gears. This is very typical of our engines/trailer combos for nearly any hill larger than an overpass. I would recommend locking out 5th and 6th gears for your old combo. Keep it close to 3000rpm the time so it dos not need to downshift as often.

The 6.2L/10-spd with smaller gear spacing would do better. However, if you lose the same amount of speed in the new 8th gear, the trans will still skip a couple gears get that engine up to 3500-3800rpm to hold your desired speed. So you should pay attention to how often the trans shifts even with new truck. Start to limit the top gears. I recommend targeting 2500-3000rpm for flat highway cruising with any naturally aspirated engine. And that 6.2L will also live 300kmiles at 3800rpm.

marpel, The 5.3L and 6.2L both have AFM. I'm not hearing of issues with it in the last 10 years. Look up used 5.3L/6.0/6.2L GM trucks with >200k miles. I bet you find a lot.

[marpel]

As my current Sierra 1500/6.2/3:73 is getting on in age and will need replacing in the next year-ish, this new one is of interest. Either that or the 6.8 (I think, off the top of my head).

Two specific things - We pull a 21 foot, 4000lb fully loaded trailer, a lot between here (BC Canada) and Denver Co. and at 64-ish mph, I have to drive in 5th all the way on the flats (2300 rpm), and gear down on the inclines, of course. It just barely holds 5th and even when cresting a minor underpass, it will sometimes gear down - and I got the 6.2 because, at that time, it was the only unit that did not have the AFM, which GM were having issues with.

So, do you think the extra HP/torque will solve the 5th gear issue and allow the vehicle to stay in OD (on the flats, I realize hills are a different story)?
And, do the new vehicles still have AFM (or whatever they call it now)? And if so, have the previous issues been resolved?

Marv

[Z71K9]

I have 6.2/10spd towing Grand Design 2800BH. Total beast.

Unhitched around town 15.5mpg. Highway 20-21mpg.