Another 6.6 gas question

[LITEPHIL]

I've really been curious about this engine. I know they should have put the ten speed with it but I'd bet the six speed works pretty good. I don't see any indications that the ten will be hooked to it at least through 2021. I'm thinking by now there would be a number of folks here running this engine.
So what do you think? How's the power and mileage. I don't really care if you've had the 6.o since I've had a couple. Just digging for any info on the new 6.6.
Thanks!

[Grit_dog]

Well they’re all sold out this year, so they’re all winners!

[LITEPHIL]

Sjm9911 wrote:

LITEPHIL wrote:
Looks like Ford spanked GM pretty good with truck sales. I'd bet that the 6 speed alone was one of the reasons Ford did better.

I just looked for that info, where did you get it? All 2020 info i find is from october and says gm sells a few more trucks then ford.

Gosh, I can not find where I read that. I was just bliping through some articles and I read that they had a poor 3rd quarter. Maybe untrue and I retract that if not. But I'm sure their sales of that truck would be better with the 10 speed.
Thanks for all the input.

[Grit_dog]

^Who cares?
GM is still s ucking hind teat in the HD gasser market for power and gears..... and I like GMs , but it’s true.

[Sjm9911]

LITEPHIL wrote:
Looks like Ford spanked GM pretty good with truck sales. I'd bet that the 6 speed alone was one of the reasons Ford did better.

I just looked for that info, where did you get it? All 2020 info i find is from october and says gm sells a few more trucks then ford.

[LITEPHIL]

Looks like Ford spanked GM pretty good with truck sales. I'd bet that the 6 speed alone was one of the reasons Ford did better.

[Grit_dog]

ls1mike wrote:
Another thing is the 6L90E is better than the 6L80E. One extra clutch per clutch pack, it is 35MMs longer than an 80E, strengthened input and output shaft with wider gears. 2500HD and 3500HD get the 6L90E and don't suffer the problems people encounter with the 6L80E in half tons. Heat failures and torque issues due to AFM causing the torque converter to go in and out of lock up.

The 90E first gear is 4.030 vs the 80Es 2.482. That was a huge improvement. 4th gear is 1 to 1 in the 90E and the 80E is 3rd. It diffidently improved the usability of the 6.0 for towing.

I have one of each at home. The 90E is in my truck. The 80E is in my 2014 Caprice PPV (never in police service) The 80E is behind a 400RWHP/400FT/LBS of torque 6.0.

But totally apples to oranges, save for the clutches and shafts being "stronger".
One is built to haul trailers, the other is built to haul @ss!

But you know that already, and in a half ton, the deeper first gear isn't needed with smaller tire diameter, lower designed duty cycle for towing, lower towing "rating" and built more for cruising than towing...the reason everyone berates half tons here.

However, I've never had issue getting 14klbs trailer moving with my 6L80E, other than the tq converter was defective since day 1 and it would shudder getting a larger trailer moving....up until it cut loose at about 60k miles! New trans does not shudder now.

[ls1mike]

Another thing is the 6L90E is better than the 6L80E. One extra clutch per clutch pack, it is 35MMs longer than an 80E, strengthened input and output shaft with wider gears. 2500HD and 3500HD get the 6L90E and don't suffer the problems people encounter with the 6L80E in half tons. Heat failures and torque converter issues due to AFM causing the torque converter to go in and out of lock up.

The 90E first gear is 4.030 vs the 80Es 2.482. That was a huge improvement. 4th gear is 1 to 1 in the 90E and the 80E is 3rd. It diffidently improved the usability of the 6.0 for towing.

I have one of each at home. The 90E is in my truck. The 80E is in my 2014 Caprice PPV (never in police service) The 80E is behind a 400RWHP/400FT/LBS of torque 6.0.

[wnjj]

wowens79 wrote:

goducks10 wrote:

GDS-3950BH wrote:
I don't get the 10 speed OCD discussions. I drive a different truck every day at work, all 3 US flavors and probably almost every combination at one time or another. Unless your always in Flatlands running empty/not towing and going for squeezing every last drop for fuel mileage, all those extra gears are wasted fluff. In hill country loaded or towing you'll never be up in them much if at all and it does not matter what is in front of the tranny. More gears = more heat and more parts to wear.

Mostly agree. Regardless of gears you still need the same HP/TQ to climb a mtn or cruise the interstate.
However an 8sp or 10 speed will have better spacing between gears and allow the vehicle to maintain speeds easier without lugging or over revving.

Exactly, with my 4 speed GM 6.0 when it down shifts its a 1000 rpm jump. I have so many times that it would be great to have a gear in the middle.
When I'm running on flattish interstate I've have to choose between struggling at 2000 rpm, and reving at 3000rpms, but it be great to have a gear at 2500rpm. I've pulled from ATL to the FL Keys turning 3000rpms and it did fine, but 2500rpms would be perfect.

Considering gas engines have such a wide range of RPM between working with loads and cruising for mileage when empty, the more gears the better. When the 6-speeds came out, they mostly improved the empty cruising with 2 overdrives instead of 1. The grade pulling gears aren't really that different.

When comparing the 6L80E to a 4L80E for example, the 6-speed adds a lower 1st gear but 2-3 are similar to what 1-2 were on the 4 speed. 4th is 15% lower than 3rd was. So practically speaking you didn't gain much in terms of useable hill climbing gears. More would definitely be nice.

[ls1mike]

I have test drove 2. It wasn't enough for me to get rid of my 17 3500HD gasser.

I would wait for at least the 4.10s. It has more low end then my 6.0 but I think to use the extra power it needs 2 more gears and 4.10s and It will stay nicely planted in the powerband.

I went from an 02 2500HD gasser to a 2017 3500HD gasser, the two extra gears make a huge difference. Both trucks have 4.10s. I notice that certain hills were I would see 4500 rpm in the 02 I barely crack 3300 in the 17. I am sure the extra power helps, but those 2 gears made a big difference.

[wowens79]

goducks10 wrote:

GDS-3950BH wrote:
I don't get the 10 speed OCD discussions. I drive a different truck every day at work, all 3 US flavors and probably almost every combination at one time or another. Unless your always in Flatlands running empty/not towing and going for squeezing every last drop for fuel mileage, all those extra gears are wasted fluff. In hill country loaded or towing you'll never be up in them much if at all and it does not matter what is in front of the tranny. More gears = more heat and more parts to wear.

Mostly agree. Regardless of gears you still need the same HP/TQ to climb a mtn or cruise the interstate.
However an 8sp or 10 speed will have better spacing between gears and allow the vehicle to maintain speeds easier without lugging or over revving.

Exactly, with my 4 speed GM 6.0 when it down shifts its a 1000 rpm jump. I have so many times that it would be great to have a gear in the middle.
When I'm running on flattish interstate I've have to choose between struggling at 2000 rpm, and reving at 3000rpms, but it be great to have a gear at 2500rpm. I've pulled from ATL to the FL Keys turning 3000rpms and it did fine, but 2500rpms would be perfect.

[goducks10]

GDS-3950BH wrote:
I don't get the 10 speed OCD discussions. I drive a different truck every day at work, all 3 US flavors and probably almost every combination at one time or another. Unless your always in Flatlands running empty/not towing and going for squeezing every last drop for fuel mileage, all those extra gears are wasted fluff. In hill country loaded or towing you'll never be up in them much if at all and it does not matter what is in front of the tranny. More gears = more heat and more parts to wear.

Mostly agree. Regardless of gears you still need the same HP/TQ to climb a mtn or cruise the interstate.
However an 8sp or 10 speed will have better spacing between gears and allow the vehicle to maintain speeds easier without lugging or over revving.

[LITEPHIL]

I guess I should mention that most of my towing is in the Arizona mountains with many 6-7% grades.

[LITEPHIL]

GDS-3950BH wrote:
I don't get the 10 speed OCD discussions. I drive a different truck every day at work, all 3 US flavors and probably almost every combination at one time or another. Unless your always in Flatlands running empty/not towing and going for squeezing every last drop for fuel mileage, all those extra gears are wasted fluff. In hill country loaded or towing you'll never be up in them much if at all and it does not matter what is in front of the tranny. More gears = more heat and more parts to wear.

I agree on most of what you are saying but the 10 speed has 7 gears before it hits the overdrives. I went from a 6.0 4 speed to my 5.3 8 speed and its always got the right gear for towing. So I would rather have the 10 than the 6 but if its not available then I may end up with the 6 speed. It has 4 gears before the 2 over drives.

[Grit_dog]

GDS-3950BH wrote:
I don't get the 10 speed OCD discussions. I drive a different truck every day at work, all 3 US flavors and probably almost every combination at one time or another. Unless your always in Flatlands running empty/not towing and going for squeezing every last drop for fuel mileage, all those extra gears are wasted fluff. In hill country loaded or towing you'll never be up in them much if at all and it does not matter what is in front of the tranny. More gears = more heat and more parts to wear.

So what you're actually saying is you don't have a clue what the advantages are, based on your perception of "never being up in them gears" anyway.
Allow me to help you understand.
1st gear is considerably deeper than the 6 speed (which is already decent 4.03 vs 4.70). = better in that hill country and loaded/towing which you're all about.
Upper gear or gears, you're not up in "them gears" with either trans if you're pulling a hill. Difference is you're keeping out of 5th and 6th with the right load/conditions vs not getting into 8th-10th gear.

BUT WAIT, there's more!

You're the hill country, loaded and towing kinda guy, right? Want to keep the engine closer to the peak powerband more often? Guess what? After you get going easier in a lower first gear, you then have 6 more gear splits before you get into "them gears", vs 3 more with a 6 speed.
The upper gears are no taller either (well 10th is marginally taller, .64 vs.67 or something like that). It's not like the 10 speeds are geared to cruise at 130mph at 2000 rpms, lol.

So actually, you have it almost completely backwards. IF you're only driving unloaded in flat terrain, less gears in NOT a hindrance whatsoever....to the point that the 8 and 10 speeds will skip shift under light load conditions.
BAM, it's a 6 speed when you're driving Miss Daisy and a 10 speed when you're a wanna be Ice Road Trucker!

Maybe this will clear it up for you...or you could just yell at me and tell me to get off your lawn!

Long live the Powerglide!!!!!