Suburban with 6.0L and 6 speed tranny?

[captnjack]

Have a Rockwood Roo 233S. Fully dry weight about 4500 so I'll probably be pulling almost 5500 pounds loaded. Currently own 2007 Lincoln Mark LT with 5.4L, 4 speed tranny, factory towing package and 3.73 axle. It's rated for 8600 pounds. Well I just did a run from NYC area to Vermont and did not at all like the feel of it on uphills. Not talking about major mountains here, just interstate. Really felt like the truck was struggling to find a nice balance between engine and tranny.
Thinking about the Suburban with 6 liter and 6 speed. Any body have any experience with it?

[kw_00]

Love my 6.0 and 6 speed, pull closer to 10k and it tows excellent. Holds 5 gear mostly in florida, Love this combo. Will keep this truck a long, long time.

[Taco]

What I do with my silverado which has the same engine and transmission as the 2500 suburban.

I have an ultra gauge which is the same as a scan gauge. I set it up to show engine load. When I approach a hill I push the pedal to get it to 100% load, any more and it will down shift, any less and you are not giving it full effort in the gear you are in. If it starts to lose speed at 100% load in 5th then I will push it harder to let it downshift when I get to about 60. This puts it into 4th then I push hard enough to get to 100% load, 4th at 60 runs 2800 rpm, this will climb most interstate grades with my trailer which is a good bit heavier than yours. On a long grade I might need to let it go to 3rd, so if it drops to 55 or so I push harder to get 3rd and let it run 100% load. I never have ever had to drop below 3rd on the interstate. I can pull my 8000lb trailer at least 55 mph up any interstate grade I have ever come across without exceeding 3500 rpm. If you want to go 65 up any eastern interstate grade then it will do it in 3rd at 4100 rpm. Your trailer is lighter it might do many grades in 4th.

What I don't do. I DON'T TRY TO ACCELERATE UP A GRADE. The truck will do it but it isn't worth the fuel. I don't go easy on the pedal trying to avoid a downshift when I know it can't pull 5th gear up the hill only to have to floor it when it gets down to 45. Then it downshifts and starts to accelerate again, but the rpm freaks me out so I let off again and lose speed. From what people on this board describe this is how they drive a gas truck in the hills. They freak and let off when it downshifts and lose tons of speed.

I also want to mention that the suburban and my silverado have an electronic throttle. The pedal isn't directly connected to the throttle plate. The pedal is more of a request to the computer to go faster or slower. I can set the ultra gauge up to show throttle plate opening and it does not directly correlate to my right foot.

[captnjack]

Taco wrote:
What do you want it to do in the mountains? Do you want to be able to go the speed limit. Do you want to be able to go the speed limit and not exceed 3000 rpm?

What did your truck do that you didn't like. Did it go too slow with the pedal to the floor or did it rev to 4500 rpm and this made you uncomfortable but it still kept speed up?

Didn't like the high revving and tranny jumping in and out of gears. I'm pretty new at this so I'm sure I could get better and get more used to it. But it really didn't feel right. Don't know how else to say it. Mileage was probably about 9mpg at best, which I suspect is not too good for my relatively light trailer. And I'm not looking to go 70 mph up hills and down hills and everything in between. I believe the 5.4 L is fine but the tranny could probably be better.

Had the truck and tried to match the trailer to it. I guess I just thought it would perform better. I plan to go out west for a good chunk of next summer and I want to feel comfortable wherever I drive.

And Thanks for the responses.

[Taco]

What do you want it to do in the mountains? Do you want to be able to go the speed limit. Do you want to be able to go the speed limit and not exceed 3000 rpm?

What did your truck do that you didn't like. Did it go too slow with the pedal to the floor or did it rev to 4500 rpm and this made you uncomfortable but it still kept speed up?

[captnjack]

ktosv wrote:
That should be a really nice pairing in my opinion. While I don't have a Suburban, I do have the 6L and 6 speed and really like the set up. I am towing a TT that has 820# of tongue weight and 6400# axle weight and really like the way it tows. It pretty much tows all of the time in 5th.

How do you do in mountains?

[3_0charlie]

That would be a Sub 2500. Would love to replace my '04 Expy with a used one (MY 2008+), but they are basically non-existant 'round here....

To answer your question, it would tow your Roo effortlessly.

[ktosv]

That should be a really nice pairing in my opinion. While I don't have a Suburban, I do have the 6L and 6 speed and really like the set up. I am towing a TT that has 820# of tongue weight and 6400# axle weight and really like the way it tows. It pretty much tows all of the time in 5th.