3/4 ton Suburban with 8.1L V8

kd7kmp

Registered User
Location
Springville, UT
Hey all,

I've been thinking for a while now about getting a 3/4 ton Suburban with the 8.1L V8. I've got couple I'm currently looking at right now. This is a rig I'd use to tow a camper, ATVs, UTV, etc as well as haul all the scouts to and from activities (maybe 3k - 4k miles a year). I currently have a 1990 GMC Suburban with 3/4 ton axles that I swapped in a few years ago. It's a good truck, but It's getting old and I tire of the the really noisy, bouncy ride when all I really do is pound pavement and graded dirt roads. Plus, when heading up any kind of hill with a moderately loaded trailer it really struggles to keep speed. We don't currently have a camper to tow but are looking and I really want a vehicle that will tow it confidently while being comfortable.

Anyhoo, I'd appreciate any advice you all my have on this. What type of issues ought I to look out for? I'm not too concerned about fuel economy as I only get 12-13 mpg unloaded with my current 'Burb (maybe 15 mpg on a REALLY good day).

Kevin

P.S. I'm not too interested in a pickup or a diesel...cost of ownership, for the amount it would be used, would be too much. This won't be a DD.
 
With an 8.1 burb you get a LOT of bang for the buck. Dempsey (Turbominivan) just went down this road and loves his. I really liked my '99 with the 7.4, 4.10 gears and G80. RPO codes to look for: GT5 is 4.10, GT4 is 3.73, G80 is the Eaton Gov-lock, which in a 3/4ton is a decent option to have. Invisible until you need it, magically appears with a thunk and does the job, then goes away until the next time.
 

TRD270

Emptying Pockets Again
Supporting Member
Location
SaSaSandy
Not sure if your just a chevy guy, but the Ford excursion with a V10 might be a good option as well. Swap out rear springs for truck springs (I know there is a thread about this somewhere) and you have a solid rig. Just another option to consider
 
Not sure if your just a chevy guy, but the Ford excursion with a V10 might be a good option as well. Swap out rear springs for truck springs (I know there is a thread about this somewhere) and you have a solid rig. Just another option to consider

x2.

Once the Excursion suspension is "corrected", it is a great vehicle.

I didn't really consider adding the truck springs (B) when I did the bags on my eXcursion since many with trucks do bags anyway, but that's a definite option. Front U's or V's and rear B's and/or bags. The other thread has a guy that can get you the springs too.
http://www.rme4x4.com/showthread.php?97001-Ford-Super-Duty-front-and-rear-leaf-springs

I did bags with a tank so that I can run them at 30psi or so when not towing and 50-70 when towing. And I can adjust the rear ride height with them, so as I have added more lift in the front all I need to do is pump the back up a little.

I never felt like I needed bags with my 2500 suburban, the rear springs were legit. I think that the 8.1's came with the Autoride package that uses airbags or airshocks to keep it level.
 

TurboMinivan

Still plays with cars
Location
Lehi, UT
I've been thinking for a while now about getting a 3/4 ton Suburban with the 8.1L V8.

Somebody rang? :)

This is a rig I'd use to tow a camper, ATVs, UTV, etc as well as haul all the scouts to and from activities (maybe 3k - 4k miles a year).

Not that you didn't know this, but the 8100 Burb will work very well for these duties. When paired with the 4.10 axle ratio (which is what I have), the 8100 is rated to tow 12,000 pounds. If it only has the standard 3.73 gears, the rating drops to a still-significant 10,500 pounds if I recall correctly. You'll have plenty of room for people and cargo, of course. For one do-it-all rig, the HD Burb is a fantastic workhorse.

I currently have a 1990 GMC Suburban with 3/4 ton axles that I swapped in a few years ago. It's a good truck, but It's getting old and I tire of the really noisy, bouncy ride when all I really do is pound pavement and graded dirt roads. Plus, when heading up any kind of hill with a moderately loaded trailer it really struggles to keep speed. We don't currently have a camper to tow but are looking and I really want a vehicle that will tow it confidently while being comfortable.

The HD Burb is gonna make you feel like you died and went to towing heaven. My observations when towing my Jeep to EJS addressed every one of your concerns I bolded in the above quote. The ride was smooth, quiet and extremely comfortable; it towed my load (est. 5800 lbs GTW) securely and safely; it maintained whatever speed I desired (which was reasonable, as I drive conservatively while towing) no matter how steep the hill.

Speaking of, I'll share some details. With my 4.10 gears, 65 MPH equates to 2300 RPM cruising in 4th gear. I used tow/haul mode all the while, yet the rig would hold 4th gear up small hills without effort. On steep hills, it would simultaneously unlock the converter and drop to third gear, then the converter would re-lock when my speed leveled off; I would then climb the hill at 60 MPH while turning 3000 RPM. Cresting the hill, the trans would upshift and I'd return to 2300 at 65 MPH. Between Moab and Lehi, there were only 3 or 4 hills which would cause a downshift--the rest of the trip was in 4th gear.

My return trip was on a sunny day with ambient temp in the low 70s. I was not running A/C. The coolant temp stayed dead on 200^ all the while, and the trans fluid temp was similarly steady at 170^. Even in 3rd gear for long uphill pulls, neither temp needle moved. The HD Burb was made to tow and tow well.

Fuel economy: on my EJS trip, I calculated 10.3 mpg over the entire trip. That's one of the fun things about Chevy V8s and towing: all the engines (8.1, 6.0, 5.3) seem to get the same economy when you're actually towing a significant load. The smaller engines will certainly do better when not towing, but since this was my dedicated tow rig I decided to go for the engine that would best handle a load. I have absolutely no regrets about my decision. (Related side note: at Moab, I shared a camp site with John who towed his similar Jeep on his similar trailer behind his Lincoln Navigator with a 5.4L DOHC V8. He observed the exact same 10.3 mpg on his trip that my 8100 achieved.)

With an 8.1 burb you get a LOT of bang for the buck.

That's a perfect summary, for sure.

Oh, you guys were talking about suspensions. Here is a shot of my Burb with my trailer attached:

trailer1.jpg


You'll notice a bit of rake--the tail sits a little higher than the nose. My Burb has the AutoRide suspension, but when I bought it the system wasn't working (the 'service ride control' warning is illuminated). I snooped around to find out what was wrong, and I learned that the former owner had replaced the front air shocks with aftermarket non-air shocks. Since the shock connectors are just hanging there, the computer is upset and thus the system is disabled.

I had initially thought about getting it working again, but then decided to use my Moab trip as a test--how well does the suspension work without the computer control? The answer is simple: damn fine. Even with 600 pounds of tongue weight, the rear end only sagged by about 3/4 of an inch... seriously. The HD springs in this rig are very sturdy and are clearly up to the task of dealing with the rated load. Since it works so well, I've decided to not revive the AutoRide at all. (Now I just need to find a way to disable that warning message.)

Long story short: if you think an 8100 Burb might suit your needs, I will wholeheartedly tell you to go for it. :thumbs:
 
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sixstringsteve

Well-Known Member
Location
UT
If I ever decided to get a tow rig, an 8.1 Suburban would be at the top of my list. Make sure you keep an eye on the t-case. The chains like to eat through the case.
 

kd7kmp

Registered User
Location
Springville, UT
Guys,

Thanks for all the responses. I've really been very happy with my current 'Burb, but it's time to replace it (it'll be for sale...;)).

Turbo,

Thanks for the detailed report on how yours has been treating you. Most that I've seen with the 8100 have Auto Ride on them. I'm sure it works great, but I've also read a lot about system failures, although the repairs don't seem to be too expensive.

Steve,

What's the issue with the chain in the t-case? Does it stretch or is there an easier fix?

Kevin
 

TurboMinivan

Still plays with cars
Location
Lehi, UT
Most that I've seen with the 8100 have Auto Ride on them. I'm sure it works great, but I've also read a lot about system failures, although the repairs don't seem to be too expensive.

When I first wanted to troubleshoot the system, I thought it was odd that nearly every google search pointed to a page telling you how to disable the system rather than repair it. Now that I see how well the HD suspension works without AutoRide--and knowing that some of the components are pricey--it all makes sense.

What's the issue with the chain in the t-case? Does it stretch or is there an easier fix?

It's actually not a chain issue at all. What happens is the fluid pump flange can wear a hole through the magnesium case. There is a cheap and relatively simple fix--the part is only $23--though it requires opening the case to install it:

http://www.thedieselpage.com/reviews/tcase.htm
 
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