[iptman]

Hello everyone,

I recently picked up 2 GMT800 Suburban 2500s. One is a 2003 with the 8.1 and 3.73 gears, 160k miles, LT trim with a sunroof (I really dislike sunroofs for the potential for leaks). The other is a 2004 with working Quadrasteer, 6.0 and 4:10 gears (obviously), 175k miles, LT trim with no sunroof and factory DVD player. I bought the 8.1 out of Seattle and it spent most of it's life in California. The QS I found on a lot in Houston before the 8.1 was even delivered and it spent it's whole life in Texas. I flew down to Houston and drove it home 1600 miles over 2 days. Both are spectacularly rust free but the QS is by far more so. It doesn't even have the typical light surface rust you'll often fond on trucks this vintage. The 8.1 has a couple dents in the body work but being the dark gray that it is they're not really noticeable. The leather is also shot and will need the front and middle rows redone. The QS body is near flawless and other than a few small issues so is the interior although it was definitely smoked in. The 8.1 needed new oil lines and while I was pulling those out I cracked the end tank on the original radiator so that led me down a rabbit hole of "while you're in there you might as well..." So along with the oil lines and radiator (still looking for an OEM) I'm replacing the water pump, front main seal, all coolant hoses, heater hoses and tees, coolant expansion tank, belts and tensioners. The QS radiator is weeping a little on one side so I'll plan to replace that along with all belts, tensioners and the coolant tank.

After buying all the replacement OEM parts for the 8.1 I'll still be less in to the 8.1 than I am in the QS but if I keep the 8.1 I'll replace the leather and that'll essentially equal out cost. I have a family of 6 with the 4 kids aged 5 to 12. My goal is to comfortably carry my family, all our gear and tow an RV capable of sleeping all of us (8000 pounds), or a boat big enough for us and friends (think Yamaha 25 footer, ~6500 pounds). I also have a compact tractor that weighs in the 4000 pound neighborhood so towing that on a steel trailer, along with implements maybe 7000 pounds. Basically I don't ever want to NOT be able to tow something I want to tow. Initially I was thinking I'd like the QS a lot more but now that I've put so much time and money in to the 8.1 (those oil lines SUCK!) it seems I should consider keeping it instead. To be fair, I only drove the 8.1 a few miles before diving in to all the repairs (I hate oil leaks) and I'm still a couple weeks out on getting it all buttoned up. The QS did great on the drive home from Houston. It was comfortable driving and I never really felt any road fatigue. And the 4WS certainly came in handy pulling in to the In and Out Burger before I left Houston. I've done a lot of research on the QS and know parts are hard to come by but this thing is so clean I just don't see having any issues with it for years to come. I like to keep my vehicles for a long time so I'm interested in longevity and above all else reliability.

So what do you guys think? Keep the 8.1 or the Quadrasteer, and why?

 

[OkDually]

Welcome to DieselPlace

I vote you keep the Quadrasteer

It's a good collector item to have

 

[DEWFPO]

Both have their advantages. I see reasons to keep both. Will you be towing in the mountains much or driving at high altitudes? The 8.1L will perform better for you under those conditions. If mostly flat towing or lower altitudes the 6L will be just fine.

 

[john61ct]

QS sounds like the better family car, keep it looking nice

8.1 is the workhorse you let get trashed aesthetically

 

[iptman]

Yeah I guess I could have put a 3rd option of "keep both" but I'm assuming that's all the responses I'd get.

 

[ancho]

I vote 8.1, for the mechanical simplicity of NOT having the Quadrasteer 10+ years down the road.

 

[biotec]

8.1 is a real horse but they are hard on fuel mileage. My buddy had one in his company truck and said there wasn't anything that it couldn't tow, just make sure there is a gas station near by. If fuel economy is not a big issue, this would be the simplest vehicle to own.
The 6.0 sounds like a nice vehicle but the QS could become a real issue with parts since that is a rather rare option.

 

[Liza007]

I've had both the 2003 and 2004 Yukon XL 6L
and both weren't that awesome towing. They got decent mileage but even with just me and the dog, they struggled towing the camper.
Don't forget that the weight capability is both the trailer and your gear in the vehicle. The 8000# camper is too much for the 6L (mine is 8k and again it struggled) and you've got the family. Also, if memory serves, the qs option doesn't have the higher towing capabilities as the 4x4 or 2wd
If you can afford to keep both on the road, save the 8.1 for the camper and the 6L for the daily drive and such.

 

[Liza007]

Ps,
Buy seat covers if the seats bother you. You will never get any return from replacement seats and the first time the kids spill a soda, you won't have a stroke

 

[iptman]

Do you know who makes decent seat covers?

 

[iptman]

Well, apparently the water pump is NLA but thankfully I found one on the shelf at a dealer in the far south east corner of Virginia, and they were willing to ship it. I also finally tracked down a radiator in Mississippi. It seems some parts for the 8.1 are becoming scarce. The radiator I took out had a sticker on it with 02/2003 on it so if I can get 17 years out of this new one I'll be in good shape.

 

[Liza007]

Do you know who makes decent seat covers?

I used to get the universal ones from Cabelas which worked great for hunting and wet dogs
Another place for parts is Amazon and ebay. Even the seats if you want to go that route.
I Would take a photo of the RPO code sticker in the glove box. Keep it on your phones.. That's the Bible for what will fit the trucks.
As much as you love these trucks, at the end of the day, insurance will value them at less than 5k. Believe me, I know. keep every receipt. Keep them safe and comfortable but you'll never see a return on new seats vs engine work

 

[Liza007]

Chevy 8.1L Vortec Common Engine Problems - Vortec 8100 V8

How reliable is the Vortec 8.1? Read about reliability and common problems on Chevy'y 8.1L Vortec Engine produced from 2001 to 2006.

chevytrucks.org

While I haven't gone through the whole site, I thought this was interesting.

 

[iptman]

Yeah I've read through that and about all I can find on the 8.1 and Quadrasteer.

 

[Tommygunner]

Re seat covers. seatcoversunlimited.com Make the best seat covers I have ever used. I have put them in 2 trucks and 1 car. They fit , look great, and wear like iron. I have a set of their Heavy duty Dorchester line in my 98 GMC that are over 10 years old and still look great. Their Scottsdale line are good strong covers that can withstand kids and dogs and look like OEM GM fabric.
Made in USA.

 

[iptman]

I just got done doing a mess of work to the 8.1. New radiator, water pump, all heater and coolant hoses, coolant reservoir, t-stat, oil cooler lines and fittings, front timing cover/crank seal, all tensioners, all pulleys, fan clutch, belts, reman ACD alternator, fresh Dexcool and an oil change with ACD PF454 filter, all 4 rotors and pads. All OEM parts except the Gates drive belt and brake pads/rotors (Napa coated/Akebono). I also put on a set of 275/75/16 KO2s. This think is so smooth and powerful it'd be tough to let it go. The steering is tight and balanced with plenty of feedback. I figured a truck like this would have over-boosted steering but it's just right.

Quadrasteer.

Nose to nose

 

[iptman]

Unfortunately after all that it looks like the 8.1 oil pan gasket is leaking. I need to degrease it a little better and maybe use some of that UV additive to confirm. I pulled the inspection plate and there wasn't any oil on the flex plate so I don't think it's the rear main. I'm not looking forward to replacing the oil pan gasket. Based on a little research it sounds like the front diff needs to come out or drop down a bit to get the pan out. I may farm this one out to a shop if I can confirm it's the pan gasket.

 

[john61ct]

Well I guess you decided you're keeping that 8.1!

Any ideas what max GVW trailer could that baby safely haul with no payload in the truck but a jockey driving?

 

[iptman]

The GCWR of the 8.1 with 3.73 gears and 4WD is 17,000, max trailer weight of 10,100. With the 4.10s it'd be 19,000/12,000. Assuming about 6000 for the truck leaves 1,000 for people and gear.

 

[john61ct]

So trying to squeeze past 14,000 would be flat out negligent?

assuming great brakes of course

Insurance, legal issues set aside, just IRL