When my GMT400 isn't enough...

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JackE

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What's the overall life expectancy on a 8.1? I have had 5.7 and 7.4 go well over 200K when taken care of. I have seen many over 300K. Is the 8.1 just as stout of a creation?
 

BNielsen

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What's the overall life expectancy on a 8.1? I have had 5.7 and 7.4 go well over 200K when taken care of. I have seen many over 300K. Is the 8.1 just as stout of a creation?

I would say so, there was a couple of 2002 2500HDs for sale near me a while back, and they ranged from 280K to 320K miles. All owned by a lawncare company and they all looked new on the outside.
 

scottydl

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So what are the real world mpg numbers with a 6.0 towing a 7K lb travel trailer? I learned that they are no better than the 7.4 when you bump up the speed to 85-90 mph.

Regardless of towing capacity or mpg's, towing a trailer at that speed presents a significant risk of tire failure on the trailer. Most ST (trailer service) tires are rated at 65mph max speed. Some larger trailer tires may be upgraded to LT (light truck) by the owner, but I don't think they ever come that way from the factory. An RV tire blowout at high speeds is no picnic... I've experienced it!

To the OP. I think you are always ahead if you don't have to buy another vehicle, but in this case, I think the TBI is really limiting you. If it were me, and I chose to upgrade vehicles, I don't think I would just go a year or two newer for a Vortec. I don't feel like there would be significant enough gains to warrant the change. I would go as big as I could afford and find an 8.1 or a Duramax. If I weren't looking at the big 5th wheel that I am, I would be happy to go a bit slower down the road and stick with my 7.4 Suburban. Sightseeing is better at a little slower pace anyway!

I can't disagree with any of that really. As much as I'm tempted to put some money into my '95 TBI (or purchase of a 96-99, which I may not find in such good condition as my '95) and hope it would make a big difference... there's probably only so much I can realistically expect from that engine pulling 9k# or more.
 

TexasT

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Regardless of towing capacity or mpg's, towing a trailer at that speed presents a significant risk of tire failure on the trailer. Most ST (trailer service) tires are rated at 65mph max speed. Some larger trailer tires may be upgraded to LT (light truck) by the owner, but I don't think they ever come that way from the factory. An RV tire blowout at high speeds is no picnic... I've experienced it!



I can't disagree with any of that really. As much as I'm tempted to put some money into my '95 TBI (or purchase of a 96-99, which I may not find in such good condition as my '95) and hope it would make a big difference... there's probably only so much I can realistically expect from that engine pulling 9k# or more.
No doubt tire failure is a conundrum. This is where the sway control and weight distribution hitch are worth the money.

I come from further back starting with an 83 454/th400/4.10 suburban pulling our toy box. Single digit mpg was the rule and even unloaded around town getting 10 was something. Went to a 99 454/4l80e/3.73 and wow what a difference.

I went through a couple of the plastic end tank radiators only to have them leak again, and now have a big ebay aluminum setup. So far so good. The newer one has bee solid but as it has gotten to 200k miles a trans overhaul is in its near future. It is also getting a 411 computer swap so we can go to a more aggressive cam. I have my eye on some Gibson shorty headers and some exhaust. Ours is a keeper so it will get some interior work to fix the heated seats and the pleather/leather seating too.

I like that it has a 42 gallon fuel tank, the spare is inside the back(ever tried to get one of those down under the truck on the side of the road?), turning radius is tight and it just drives nice.

As a comparison we have an 03 2500hd pickup. 6.0/4l80e/4.10, and while it drives nice also, doesn't have the power(though it is down 1.4L of displacement) for the big trailer it tows the open car hauler fine. It just doesn't have the solid feel of the Suburban(at least to me).

A deisel swap is a pipe dream. Way too much work and cash outlay for the return. If I was to do one it would be a 4bt with turbo and lots of boost and a spicer seven speed.

If you want a diesel I'd have to say go buy a crew cab with one but by your posts you know the pandoras box of probs a used diesel out of warranty could spring on you. Just the upkeep differential turns me off the deisel route. I'm just not in that big a hurry when i'm not at work. We plan for lots of stops along the way to see the sights and enjoy the ride. Yeah, I'm that guy clogging up the highway. and pulling in front and slamming on the brakes isn't the brightest move. Just go around and keep moving.

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scottydl

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Yep I've got both weight-distribution hitch and sway control on my Suburban/trailer, along with supplemental airbags on the rear axle to soften the ride when all that tongue weight of the trailer is pushing down on the rear end. Those bags make a big difference.

What does Big Red there weigh when fully loaded?
 

TexasT

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Depends on what we bring along and where we go. Mostly it goes to the drag strip with our car in it. I bought the 28' thinking i would fit a junior dragster or golf cart in front of the car. Neither of those materialized. It has moved us to Wisconsin, and back to dfw, then to houston, then midland, then when the oil field crashed in 09 back to DFW again. I'm sure I was over what it is rated for on more than one of those trips and I'll leave it at that.

With the car, tools and such I would think it is in the 8-9k# range.

As seen above we have been through a "few" tires along the way but it has definitely been a purchase that paid for itself more than once. It doubles as a storage building since the kids are almost gone. I'm hoping to get the race car back together and be able to go more regularly.
 

Jermaine Smith

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TexasT

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It is a nice looking truck in the pix. I have a 1994 half ton in that color combo. Might be worth $8k to someone, but not me.
 
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