When I was shopping for a travel trailer, I was amazed that my truck was able to tow everything I looked at. This astounding fact was the belief of the salesman, and not exactly the truth.


I want to share what I have learned, because that's why we are in this forum! I've learned a lot here and decided to stop lurking.


The 6.0L is a very strong engine and Chevy's ratings of 8000 lbs towing with 3.73's and 10,000 lbs towing with 4.10's are doable. At those weights you will get outside your comfort zone, literally. Fully loaded with quads, coolers, & 100 gallons fresh water (I knowhttp://www.dieselplace.com/forum/smileys/Disapprove.gif) we ask our truck to tow this 8500 lb trailer. We have 4.10's and a few performance mods, chip, exhaust, 93 octane fuel! and the truck does it, even with BFG 285/75/16 oversize tires. These tires and 4.10's are combined to about equal to 3.73's and stock tires. We have had 4 trips of over 500 miles each in the past year, with no towing problems.


The truck starts to get "unhappy" on 6% freeway grades. We are forced to slow down by rising engine temps and end up in 2nd gear to make the grade at around 35 MPH. Gas mileage towing is up from 6 to 7.5 after adding the chip and the exhaust. Most of our trips include a long stretch of 200 miles of flat freeway. Honestly, if not for the hills/mountains we would not need any more changes.


Our big changes are both this week. I just had 4.56 gears installed and am getting Bridgestone Dueler A/T Revo 265/75R16E tires tomorrow. The gears made a night/day difference already and the tires, from my current 33" down to 31.8" should give me more power too. I'll be towing the trailer on Monday and will post the new experience here soon after.


Is there anyone else towing 8000 lbs+ with the 6.0L engine? I would love to hear more experiences about what mods help. The $40k truck mod upgrade to a Duramax is a good one, but not possible right now.

You are very wise with your gear choice. Let us know how it works out. I predict that towing mileage will increase with this mod. GM is too generous with tow ratings because a heavy pickup with a 6.0 and 3.73's is not a good "horse to pull 8000lbs with regularly, it needs at least 4.10's and 4.56 even better to limit the amount of downshifting below drive on steep grades. Gassers can pull some surprizing loads well if they are gear properlyEdited by: snoman

From reading threads on RV forums I think you'd do fine, even on the 6% grades if you'd just gone back to the stock tire size. You've demonstrated that GM new what it was doing when it said the 3.73s cut 2000# off the tow rating.


Your 4.56 gears will be a significant improvement and combined with the shorter tires give you a good chance of holding 3rd gear with the T/C locked, for cool and happy engine and tranny.





I've read about a supercharged 6.0 that happily towed a similar load through Texas and Colorado, so you might consider that if the $$$$ doesn't scare you off. Of course the owner of that truck eventually upgraded to a D-max.http://www.dieselplace.com/forum/smileys/HiHi.gif

GM did not really do their home work on tow rating because even 15 or more years ago they were a lot more conservative with the ratings and would have called for 4.10's at 8500 lbs to begin with in a like truck with simular power. It is all PR now. There was a time too when you could even order 4.56's from the factory many years ago and I had a 60's truck once (first one I ever had) that had factory 4.56's in it standard too. I also had a 72 GMC 4x4 with a 4sp, a 350 and 4.10's that I towed a 4 horse trailer with for many years with it and I never left 4th or lost speed on any hill I ever climbed on a interstate with it or a 27 ft travel trailer attached to it.Edited by: snoman

Thanks for sharing your input on this topic. The most I have pulled with my truck is around 5500lbs worth of a trailer. The truck pulls it just fine. The 6.0L is a good motor and can pull what it is rated for, but the economy of the motor does suffer. The gear change should help you out a bunch. The Dmax is a better puller without a doubt, but the cost is a big factor like you said. I am happy with the performance of my 6.0L, but would love to have a diesel one of these days and a nice 5th wheel trailer to go along with it...http://www.dieselplace.com/forum/smileys/HiHi.gif Edited by: Chevyfreek

I've got a 6.0L Suburban 2500 I just picked up. I specifically opted for the 4.10s since that was the only option other than 3.73s.

Now I haven't started to tow yet, but I can say this...my Impala SS was towing a 6300lb RV with 3.73s. The engine was more than up to it. The 4L60E was having a rough time, not impossible, but it was clearly hard on the trans.

I know somone that tows a 5500lb RV with the 6.0L in a 2000 Silverado with 3.73s. Don't even know it's back there, even on hills, etc.

I'm expecting great things from the 4L80e and the semi-floating rear axle 4.10s with the 6.0L.

Although GM clearly states my truck will tow 9600lbs, even if it could, I usually try to stay at **about** 1000lbs south of that number. Currently with passengers, cargo, RV, etc, I'm not anywhere near the 9600lbs.....yet. :)
Edited by: Silvertwinkie

I have towed 7000#-8000# a few times without a problem. The truck did have to take a bit more gas but is not straining for power. Plenty of pushing power for snowplowing too. http://www.dieselplace.com/forum/smileys/Approve.gif No modifications made yet that would affect the power, towing, etc. Edited by: wxmn6

I have towed 7000#-8000# a few times without a problem. The truck did have to take a bit more gas but is not straining for power. Plenty of pushing power for snowplowing too. http://www.dieselplace.com/forum/smileys/Approve.gif No modifications made yet that would affect the power, towing, etc.

I have pushed snow with 6 bangers. Contray to popular belief, it does not take a lot of power to push snow, just proper gearing and traction. 7 or 8k would work with 4.10's and a 6.0 of fairly flat ground but in seriously hilly areas, it would be hurting. I like to be able to never go below drive on a hill on interstate or a major road hill with a load to maintain speed when towing.

Book says GMC Sierra 2500HD with 6.0 gas and 4.10 will pull 10,200. After reading these posts I 'm not sure GM is right??

That is correct, both Chevy and GMC 2500HD with 6.0L gasser and 4.10 gear will have towing rating of 10,200# - However the light duty factory hitch is only rated for 7500# without sway bars so you might want to upgrade that wimpy hitch with a beefy aftermarket hitch such as Drawtite, Reese, etc that has Class 4 with rating of 10,000#.

Thanks wxmn6. I'm pulling a 9,200# 5th wheel with Reese 15,000 hitch. Seems to pull ok but have a terrible shudder on take off that quits about 15 mph.


Bob

Thanks wxmn6. I'm pulling a 9,200# 5th wheel with Reese 15,000 hitch. Seems to pull ok but have a terrible shudder on take off that quits about 15 mph.


Bob

I am beginging to suspect rear ujoint angles here. Also check the joints themselves. There is a lot of torque on the rear shaft at startout and I think housing is wrapping up a bit on startup causing shudder. Regardless of what GM says you are about at limit with factory gearing (or beyond it if you tow in a hilly area) for that weight and they do not factor in wind drag in total load in their ratings beacause 10k on a flatbed trailer is easier to pull than a 10k fifthwheel TT at speed.

Here is the update on my truck's towing capacity since last week. We towed the trailer in today for an unrelated service visit. I would estimate the trailer weight at around only 7000 lbs since it was very unloaded. Our last 5hr trip was without ATV's & 100gal water, so the comparison is fair.


Since the trip at the end of July we changed the gears from 4.10 to 4.56, added a 24,000 GVW tranny cooler, and downsized the tires from BFG 285/75/16 to Bridgestone Dueler Revo 265/75/16.


The short answer is we are Happy!http://www.dieselplace.com/forum/smileys/Big Smile.gif Performance towing around town was good before, but holding 4th gear on the freeway was a problem. Now the truck has enough power to hold 4th with no trouble. Headwinds make a huge diff with this travel trailer and we had some headwind today. We did not do a hill climb today, but I am sure that we could do extended freeway grades in 3rd now instead of having to slow to 2nd. Next time I do one, I'll post another update.

Here is the update on my truck's towing capacity since last week. We towed the trailer in today for an unrelated service visit. I would estimate the trailer weight at around only 7000 lbs since it was very unloaded. Our last 5hr trip was without ATV's & 100gal water, so the comparison is fair.


Since the trip at the end of July we changed the gears from 4.10 to 4.56, added a 24,000 GVW tranny cooler, and downsized the tires from BFG 285/75/16 to Bridgestone Dueler Revo 265/75/16.


The short answer is we are Happy!http://www.dieselplace.com/forum/smileys/Big Smile.gif Performance towing around town was good before, but holding 4th gear on the freeway was a problem. Now the truck has enough power to hold 4th with no trouble. Headwinds make a huge diff with this travel trailer and we had some headwind today. We did not do a hill climb today, but I am sure that we could do extended freeway grades in 3rd now instead of having to slow to 2nd. Next time I do one, I'll post another update.

Glad to here it worked out for you. Gears can make a world of difference with a gasser towing. Did you do a MPG check yet?

Just thought I'd throw in this as a comparison...

A few friends of mine tow between 8000 and 9100lb Airstreams with thier 6.0L. Both are claiming towing MPG with these RVs in the area of 11-13mpg. Neither really go for land speed records and have 4.10 gears.

A family member also tows approx 5800lbs also gets 12-13 towing w/ the 6.0L and 3.73s.

Now keep in mind that none of the above are towing 5th wheels...these are all conventional RVs.

I have no clue what I'll get when I tow our 6300lb Airstream, but will post when I start towing. Right now I have about 350 miles on my 6.0L Suburban K2500 w/4.10s. Around town (not towing, but with lots of stop and go) I get between 12 and 13mpg right now.

In about 150 miles, I will be doing it's first break in oil change.Edited by: Silvertwinkie

I pull my smaller equipment trailer with my Yukon XL 6.0L 4.10's sometimes. It hates the big long steep hills. But does fine everywhere else. And I can still haul 40 sheets of 3/4 inch plywood in the back.








Fuel mileage is under 10 when towing.

Snoman


I have changed all 3 u-joints, carrier bearing and the rear trany mount. Still have that shudder. I tried moving the carrier back and forth but dosen't seem to help. I starting to think it might be something in the rear end?? It seem to be worse when starting from a stop uphill and turning right. Talking about fuel miles ..I do get about 10 mpg with the heavy 5th ,(weighed it again it's at 9800# now),when towing and around 15.9 mpg at 75 -80 mph freeway speeds without the trailer.