How's Everyone Liking Their 6.0/6 Speed Combo?

Shatterz · January 21, 2008

Hey Guys

Looking get into a 08 2500 crewcab 4x4 in the coming weeks. How's the 6.0 motor as far as power (problems?) and the 6 speed trans (which to me seems like too many gears) ? I thought I read back here a while ago something about the 6l80e having some shifting issues but not sure on that???? I really won't be doing any towing but I really want a truck that got some (you know what). Also whats the general consensus between the 4.10 and 3.73 rear?

The reason I ask this is because I'm also seriously looking at a certain brand of truck with a 6.8 V10 ..........I know I know

So help to convince me to stay in the chevy camp

omegafiler · January 21, 2008

I'm sure the 6sp folks will chime in soon, but more gears is the way to go. That's pretty much the way all vehicles are going now. When done correctly, you generally get better accelleration, towing, performance, and even mileage.

Oh, and don't buy a Ford. You know, just to clear up that issue.

Zembonez · January 21, 2008

I don't own one either but all I have heard in here that was a negative was a few people having to have their control modules reflashed to cure 6 speed shifting issues. Otherwise everybody seems to be happy.

If you want to be really unhappy with your fuel economy, buy the V10. Coworker of mine had a cool V10 Excursion that gets a little over 6 MPG. He isn't real happy at this point.

2017HD · January 21, 2008

I have an 07 6L 6Sp with a 4.10 rear end. I tow a 24' TT that weighs around 5600lbs. I have had the truck just under a year and have had very little trouble with it. The worst thing was the cabin computer went out and kept the dome lights on all the time. The other item was my tailgate straps were not the same length. Both issues were fixed by the dealer with no problems. I am going in to get the TCM re flashed to get rid of the rough 2-3 shift when the tranny is cold. I get as much as 15MPG on the hy and 11 when towing the TT so the ave is around 12.5 (according to both the DIC and hand calculations). The transmission makes towing very easy - engage tow/haul, put it in D and go. It is very smart with both up and down shifting - on the flat it easily loafs in 6th with occasional shifts to 5th. I have climbed 6% grades in 4th turning 3500-4000 RPM doing 50-60MPH. I got the camper mirrors, brake controller, LT2 pkg, back-up detector, movable pedals among other things - when I got the truck it was ready to hook to my trailer (after break-in) with no additional mods. One more thing, the brake controller coupled with the grade braking feature of the transmission make downhills as easy as the uphills. It also makes stopping the rig while going through town easier. I think it will make both the truck and trailer brakes last longer. If you want to slow down, simply pump the brake once and the transmission will downshift one gear, pump again for another downshift, if you apply continous brakes, the transmission will downshift as quickly and as much as required. To upshift - simply tap the gas.

ursandal · January 21, 2008

I've got an 07 6.0 w/6 speed (3:73). Only had it for a couple months and 1400 miles. No problems at all, tranny shifts smooth, don't even notice the extra gears in daily driving. Plenty of power IMO. I'm getting around 13-15 mph mixed driving, hilly around here too. When on the freeway with cruise on at 70 mph the computer gives me 16+mpg. Haven't run a tank through it yet with strickly freeway miles.

Haven't towed with it yet so I can't comment there, just don't get a Ford....really!!

Al

davzog · January 21, 2008

I may get slammed for this, but here it goes....

I have a 2007 Classic with the 6.0 and 4.10 gears, but it has the 4L80 4 speed auto, not the 6 speed. I really like the truck and find it the most comfortable and best riding 3/4 ton I have owned...had a Dodge Cummins and a Ford with a V10.

If I was going to buy a new truck, there is absolutely no doubt that the V10 would be my choice....far superior to the 6.0 for towing my 5th wheel....the 6.0 is maxed at 10,000 pounds....steep hils are a real chore for this engine.

THe V10 pulled almost as hard as the Cummins and hills had litle impact on performance, and it did not have to run at 4000+ rpms as the Chevy does.

THe MPG was BETTER with the V10....I have never got over 14.5 on the hiway with the 6.0, but I consistently got 16+ with the V10 and 4.10 gears.

Tow the 5th wheel, the V10 got 9-11 and the 6.0 gets 7-9....dam thing is working itself to death.

I had to get rid of the Ford because it had the six speed manual tranny, and my left hip blew out and I can't handle the heavy clutch any more....otherwise, I would still have it.

Again, I like my Silverado very much, but it is no match for the V10....

The best match up would be the Chevy with the old 8.1....unfortunately it is not available anny more...dammit....

vranasaurus · January 21, 2008

I may get slammed for this, but here it goes....

I have a 2007 Classic with the 6.0 and 4.10 gears, but it has the 4L80 4 speed auto, not the 6 speed. I really like the truck and find it the most comfortable and best riding 3/4 ton I have owned...had a Dodge Cummins and a Ford with a V10.

If I was going to buy a new truck, there is absolutely no doubt that the V10 would be my choice....far superior to the 6.0 for towing my 5th wheel....the 6.0 is maxed at 10,000 pounds....steep hils are a real chore for this engine.

THe V10 pulled almost as hard as the Cummins and hills had litle impact on performance, and it did not have to run at 4000+ rpms as the Chevy does.

THe MPG was BETTER with the V10....I have never got over 14.5 on the hiway with the 6.0, but I consistently got 16+ with the V10 and 4.10 gears.

Tow the 5th wheel, the V10 got 9-11 and the 6.0 gets 7-9....dam thing is working itself to death.

I had to get rid of the Ford because it had the six speed manual tranny, and my left hip blew out and I can't handle the heavy clutch any more....otherwise, I would still have it.

Again, I like my Silverado very much, but it is no match for the V10....

The best match up would be the Chevy with the old 8.1....unfortunately it is not available anny more...dammit....

The 6L90 makes a lot of difference. The extra gears help the engine not to have to work as hard. The two overdrive gears also help the fuel economy. The LQ4 that is in your truck has a little less power and torque than the LY6 that is in the NBS trucks. It all adds up to a big difference between your truck and the the new ones.

I really like mine. I recently bought a 2007 2500HD CCSB 4X4. Researching my new truck is how I found this site. I upgraded from a 1500 simply because I got a good deal on it and I wanted a 6.0 in my new truck anyway. I only have 350 miles on it and so far I have no complaints. I really like the 6 speed as compared to my old 4 speeds.

I doubt I ever tow anything heavier than my 22' jon boat which when fully loaded weighs about 3000-3500 pounds, it won't even tax the truck in the slightest.

BIGWRENCH40 · January 22, 2008

I have had my 2008 Silverado 6.0/6 spd. for about 2 months now and have zero complaints about it. It shifts smoothly through all gears and has great power.

txdutt · January 22, 2008

I like mine, only change I would do is get the 4.10 axle. The 07's NBS trucks only came with the 3.73 rear end...

ATMINF · January 22, 2008

Just to put my 2 cents in, and to clarify I currently have a 2006 2500HD with a 6.0L and I had a 3/4ton suburban with 6.0L. For me I have always gotten around 16mpg doing between 70-80MPH on the hwy for the pickup and got about 17 mpg with the suburban. And the numbers that were posted by Davzog surprise me. I know of my father in law and my brother in law that had the V10s and they always got below 10 mpg. maybe they drove their trucks harder??

irengineer · January 22, 2008

I have an 07 6L 6Sp with a 4.10 rear end. I tow a 24' TT that weighs around 5600lbs. I have had the truck just under a year and have had very little trouble with it. The worst thing was the cabin computer went out and kept the dome lights on all the time. The other item was my tailgate straps were not the same length. Both issues were fixed by the dealer with no problems. I am going in to get the TCM re flashed to get rid of the rough 2-3 shift when the tranny is cold. I get as much as 15MPG on the hy and 11 when towing the TT so the ave is around 12.5 (according to both the DIC and hand calculations). The transmission makes towing very easy - engage tow/haul, put it in D and go. It is very smart with both up and down shifting - on the flat it easily loafs in 6th with occasional shifts to 5th. I have climbed 6% grades in 4th turning 3500-4000 RPM doing 50-60MPH. I got the camper mirrors, brake controller, LT2 pkg, back-up detector, movable pedals among other things - when I got the truck it was ready to hook to my trailer (after break-in) with no additional mods. One more thing, the brake controller coupled with the grade braking feature of the transmission make downhills as easy as the uphills. It also makes stopping the rig while going through town easier. I think it will make both the truck and trailer brakes last longer. If you want to slow down, simply pump the brake once and the transmission will downshift one gear, pump again for another downshift, if you apply continous brakes, the transmission will downshift as quickly and as much as required. To upshift - simply tap the gas.

Great comments on the trans. You've got the operation nailed to a "T".

The TCM reflash should help your rough cold 2-3 shift issue (the first one or two 2-3 shifts). It will also move the shift pattern a bit, especially the 4-5 and 5-6 shift points which are made at noticeably higher speeds. Some people were looking for more power (especially under hot conditions) and keeping it in lower gears longer should help.

You described grade braking perfectly. Did you find this operation intuitive or did it take you some time to figure out?

2017HD · January 22, 2008

My first test tow with the truck and TT was up and over a nearby 6% grade - and then return via a winding road with lots of ups and downs. I took it easy at first, and found that the simple brake tap = downshift was great on the long downhill while on the more winding road where I was on the brakes a bit more it was a bit more troublesome - but I found it easy to adapt to. What I really like is in town when I come up to a stoplight - just ride the pedal and the transmission brings me to a stop. The TCM is programmed to allow downshifts only when the RPMs are right so everything is well controlled.

s-ten · January 22, 2008

Sounds like GM took what they learned from the Allison and incorporated it into their new 6L90E. That is good news, because I know my dads Allison works like a charm with a load.