01-06 Suburban/Yukon XL 2500

[TheViking]

I'm looking for a DD/Family Trip vehicle for my wife and after checking everything from Discovery's, Land Cruiser's, 4Runner's, Expediton's, and Excursion's I finally decided on the 3/4 ton Suburban/Yukon XL. You can tow with it, haul eight large family member or five and a bunch of crap from the mall/out of town major shopping outlet stores. Also being build for heavy duty use the brakes are bigger and other driveline components.

Now I'm asking for the pros and cons of ownership and major mechanical problems seen that seem common.

I would use the vehicle to tow a trailer from time to time and slowly build it up for back country trips when I would drive it. For the engine I'm looking at the 6.0 but might jump on a 8.1 for the right price. I realize that I'm looking at vehicles with 150K to 200K and nearly a decade plus or older.

Also unlike the Ford's and Land Rover's I want something I can still work on fairly easily and not have to work on all the time and my 5.4 3V Triton has left me upset with FoMoCo.

Thanks for your time.

 

[02TahoeMD]

Greetings - you may want to do some research on some GM / Chevy related forums for more detailed information. That said, the 2000 1/2 to 2002 and then 2003 to 2006 serve as "brackets" for the NBS style full size GM SUV's / pickup trucks. They all looked the same but the 2003 model year introduced a lot of electronic changes and a slightly different interior trim package. The biggest problem I am aware of for the 03 and up trucks was the stepper motors in the instrument clusters would develop a mind of their own. By now, any used truck you are shopping for most likely will have been fixed, but just something to be aware of.

I personally like the 6.0 engine and find the GM LS V8 engine to be approachable for a shadetree mechanic. And every parts store around is going to be stocked with stuff you need for repair and if they dont have it in stock, it will be easy to obtain on order.

I understand your feelings about the Ford 5.4. I had one in my old work Expedition and the thing was a real shop hog, it ate coil packs like they were candy.

 

[TheViking]

Thank you and I have a similar post on a separate forum but its geared for crawlers and bouncers. I wouldn't be doing either with this more of an overland set up so I decided to check here after seeing a few threads on Suburban builds.

Yeah I'm Ford fan but the newer Ford engines are a poor let down compared to the older push rod style engines, more power and able to pass EPA regulations, but a major let down to owners....

 

[DaveNay]

I've got a Triton 5.4 sitting in my barn if you want it....:ar15:

 

[7echo]

What sort of MPG are possible with this era truck?

I recently purchased a 99 4Runner with 100k miles. Looked at the Suburbans but decided they were too big, particularly difficult to park. Now I am thinking maybe in the future get one like you are looking for so I will be following this thread. I need something for my son to drive in 3 years so maybe a used Suburban will fit that bill.

 

[Kaisen]

I've owned two 8.1s and three 6.0s of this vintage, all 2500-3500, but only two Suburbans. My current '03 8.1L has over 260K miles.

Known issues? Oil consumption. Light piston slap at start-up. Can have issues with transfer cases depending on abuse (I've had no issues). Transmissions and engines are generally pretty darned bulletproof. Early 8.1s (01-02) had issues with the camshaft position sensor on the back of the block, but later remedied with a new part... it would be wise to replace it and have a spare on hand (they're small and $25).

All 8.1s, and 03-06 6.0s were throttle-by-wire and could have issues where the throttle position sensor at the pedal didn't agree with the throttle position sensor at the throttle-body and would throw the truck into limp mode reading "reduced power" on the DIC. Turning off the truck for thirty seconds and restarting would reset the issue, but sometimes it signalled a real failure in the potentiometers (salt from shoes at pedal) or that the throttle blade itself was gummy. A new AC Delco throttle body w/ sensor and blade motor is $100ish for a 6.0L and $150ish for a 8.1L. The pedal TPS is much less money.

If the Sub is equipped with Autoride (automatic load leveling) looks for "Service Autoride" or "Service Suspension" as a dummy light or DIC readout (depending on year) as it meant the system was inop, either because a PO replaced the expensive air shocks with cheaper traditional shocks, OR because the air compressor failed. No biggie, you can trick the light to stay off with a resistor.

Power window regulators fail, and can weaken the motors. Knock-off regulator/motor combos are about $110 a window. The power lock solenoids can get weak, and they're $20ish each, except the rear gate which is $40ish.

If you hear/feel a disjointed 'clunk' in the steering column it might be a loose intermediate steering shaft. They can be repacked with grease, but there's also an updated part, that I *think* was pretty cheap. Same with a 'whump' sound from the rear driveshaft as you left a stoplight, a slip-yoke can get dry, and can be repacked. Neither have happened to my current Sub.

The newer 03-06 trucks have much better multiplexed electronics (as mentioned) and more features. If it's an 8.1L they have better transmissions (4L85E vs 4L80E) and better torque-management to save the transmissions from abuse. It's noticeable, though, in how responsive the trucks feel off the line. Not that an 8.41L can really be lacking. The 6.0L also feels a tad smoother and less torquey in 03-up models, simply from software programming. A tune really wakes either version, if you're inclined. I have kept mine stock.

You can choose from 3.73 or 4.10 gearing, both were available with the G80 locking rear. Decide for yourself how you're going to be using the truck and at what speeds.One gear is not better or worse than the other, just different. I prefer the 3.73 gears, but I'm typically in the minority here. I've owned both. But at higher freeway speeds the lower gear helps me keep the 8.1L pulling torque, and I get better fuel economy. Bigger tires help that too. I run a 285/70-17 (32.8") that changes the effective gearing 7-8%.

My current truck has averaged 12.2 mpg (hand-calculated from GPS) over tens of thousands of miles. Mostly towing. About 60% slow speed, 40% freeway speeds. Around town in Summer, I get about 11 mpg. Around town in Winter, about 10.5 mpg. Freeway speeds (62 mph), empty, about 15 mpg and drops to 14 mpg at 75 mph. Loaded with trailer, about 9.5 mpg around town and about 11.5 mpg freeway. As I said, it works out to 12.2 mpg over the last couple years.

With no failures in 260K miles it is hard to argue that there is a "better" truck, but easy to define your metrics that there may be a better truck for your needs. I'd recommend one in a heartbeat. Good luck

 

[Sooper Camper]

my dad has an 02 2500HD with the 8.1. a tuner, dual exhaust and 32s, other wise stock. it gets 15-16 on the freeway if you don't drive like a ********. worst mileage i've ever seen it get was in the 10-11 range towing a 6000lb crawler from California to Arizona and back. it has plenty of power, a LOT more usable torque than a 6.0 IMO. mileage is generally worse with the 6.0 from people he talks to at the gas pump. the first time you find yourself with your foot to the floor in a 6.0 you'll be wishing you waited for the bigger engine. these are not light vehicles, even when they are empty. a loaded model with 3 rows of seats is well past 7000lbs.

I'd get one, they are very reliable trucks. Only issues he's had are a few random codes here and there and failed o-ring on a transmission cooler line. The dashes come apart very easily, some of the plastic feels a little cheap IMO and if they get kept outside it can deteriorate quickly. the gauge cluster in my buddies 03 failed, my dad's 02 hasn't; but the bulbs in my dad's climate control panel are burnt out (its a sealed unit, can't replace bulbs). they are about as simple and reliable as you are going to find for a vehicle made post 2000...

 

[Kaisen]

Oh, and fuel pumps can fail if you continually run under 1/3 tank as 1) sediment is more likely to suck up into the pump, and 2) the pump is "cooled" by being submerged in fuel as a heat-sink. So when you run with little fuel in the tank, it's not cooling the pump. Again, I've had no issues with my current truck. But did with my 01 8.1L... luckily the failure signs gave me plenty of warning.

Best practice: keep it over half tank

 

[Kaisen]

And the instrument cluster failures (where a gauge fails) is remedied by $7 stepper motors and a soldering iron. Or there are places that will do ALL of the instrument cluster's stepper motors and replace all the bulbs and send it back to you for $110ish.

 

[TheViking]

Thanks for the info looks like now maybe the 8.1 is the way to go.

 

[plumber mike]

I've owned two 8.1s and three 6.0s of this vintage, all 2500-3500, but only two Suburbans. My current '03 8.1L has over 260K miles.

Known issues? Oil consumption. Light piston slap at start-up. Can have issues with transfer cases depending on abuse (I've had no issues). Transmissions and engines are generally pretty darned bulletproof. Early 8.1s (01-02) had issues with the camshaft position sensor on the back of the block, but later remedied with a new part... it would be wise to replace it and have a spare on hand (they're small and $25).

All 8.1s, and 03-06 6.0s were throttle-by-wire and could have issues where the throttle position sensor at the pedal didn't agree with the throttle position sensor at the throttle-body and would throw the truck into limp mode reading "reduced power" on the DIC. Turning off the truck for thirty seconds and restarting would reset the issue, but sometimes it signalled a real failure in the potentiometers (salt from shoes at pedal) or that the throttle blade itself was gummy. A new AC Delco throttle body w/ sensor and blade motor is $100ish for a 6.0L and $150ish for a 8.1L. The pedal TPS is much less money.

If the Sub is equipped with Autoride (automatic load leveling) looks for "Service Autoride" or "Service Suspension" as a dummy light or DIC readout (depending on year) as it meant the system was inop, either because a PO replaced the expensive air shocks with cheaper traditional shocks, OR because the air compressor failed. No biggie, you can trick the light to stay off with a resistor.

Power window regulators fail, and can weaken the motors. Knock-off regulator/motor combos are about $110 a window. The power lock solenoids can get weak, and they're $20ish each, except the rear gate which is $40ish.

If you hear/feel a disjointed 'clunk' in the steering column it might be a loose intermediate steering shaft. They can be repacked with grease, but there's also an updated part, that I *think* was pretty cheap. Same with a 'whump' sound from the rear driveshaft as you left a stoplight, a slip-yoke can get dry, and can be repacked. Neither have happened to my current Sub.

The newer 03-06 trucks have much better multiplexed electronics (as mentioned) and more features. If it's an 8.1L they have better transmissions (4L85E vs 4L80E) and better torque-management to save the transmissions from abuse. It's noticeable, though, in how responsive the trucks feel off the line. Not that an 8.41L can really be lacking. The 6.0L also feels a tad smoother and less torquey in 03-up models, simply from software programming. A tune really wakes either version, if you're inclined. I have kept mine stock.

You can choose from 3.73 or 4.10 gearing, both were available with the G80 locking rear. Decide for yourself how you're going to be using the truck and at what speeds.One gear is not better or worse than the other, just different. I prefer the 3.73 gears, but I'm typically in the minority here. I've owned both. But at higher freeway speeds the lower gear helps me keep the 8.1L pulling torque, and I get better fuel economy. Bigger tires help that too. I run a 285/70-17 (32.8") that changes the effective gearing 7-8%.

My current truck has averaged 12.2 mpg (hand-calculated from GPS) over tens of thousands of miles. Mostly towing. About 60% slow speed, 40% freeway speeds. Around town in Summer, I get about 11 mpg. Around town in Winter, about 10.5 mpg. Freeway speeds (62 mph), empty, about 15 mpg and drops to 14 mpg at 75 mph. Loaded with trailer, about 9.5 mpg around town and about 11.5 mpg freeway. As I said, it works out to 12.2 mpg over the last couple years.

With no failures in 260K miles it is hard to argue that there is a "better" truck, but easy to define your metrics that there may be a better truck for your needs. I'd recommend one in a heartbeat. Good luck

Fantastic post. Thanks for the info. These are the only issues I've experienced. I picked up a gently used HIGH mileage one for a song, from a friend. The 8.1 is a bit thirsty, but you don't feel cheated like a 6.8 V10 ford. You know exactly where that gas goes. It really delivers in the power department.

 

[rayra]

I would urge you to reconsider your engine criteria. We've had a '99 Tahoe and now an '05 Tahoe, both 1500s with the 5.3L Vortex and the Z-71 package with its upgraded components. That includes heavier-duty brakes and a Class 4 towing package (500# tongue weight, 12k# tow weight). We've done the 'daily driver / occasional towing' throughout, including regular towing trips over the 'Grapevine' in SoCal and the Sierras, and they've performed ably. Last big tow was emptying out a sold house in the Sierra foothills with a dual-axle 14' U-Haul, packed full. Towed like it wasn't even there. Likewise road trips from SoCal to Albuquerque were good at 16mpg cruising down the highway. Getting around 14.5mpg commuting in L.A. Put 130k+ on the '99 and over 144k on the '05 now and it's still going strong, not leaking a drop. Water pump is the only thing we've had to do to it, aside from regular maintenance.

I too had set my sights on a K2500 suburban as my 'project' vehicle, using much the same criteria as you've expressed. I was sure I wanted the heavier duty brakes and the 4L80 trans. But I had some trouble finding any that didn't have the big fuel-sucking motors (8.1/454). But ultimately I just recently purchased an '02 K1500 LTZ Suburban with all the options and comparatively low mileage of 116k, overall in great shape for $5300. And it too has the 5.3L. I'm happy to have it. I've just finished doing the equivalent to a 100k mi service to it and I think it will do all I ask of it, which is pretty much the same as your criteria.

To the poster worried about the size / parking, the Suburban is almost exactly the same wheelbase and overall dimensions as a full-size longbed pickup. I've been daily-driving and parking one of those for ~28yrs 360k mi. It isn't that difficult.

Looks a little silly having His & Hers SUVs, but you can see all three in this pic -

In closing to the OP, consider the 1500-class. There are some out there with the 6.0L as well.

 

[TheViking]

I would urge you to reconsider your engine criteria. We've had a '99 Tahoe and now an '05 Tahoe, both 1500s with the 5.3L Vortex and the Z-71 package with its upgraded components. That includes heavier-duty brakes and a Class 4 towing package (500# tongue weight, 12k# tow weight). We've done the 'daily driver / occasional towing' throughout, including regular towing trips over the 'Grapevine' in SoCal and the Sierras, and they've performed ably. Last big tow was emptying out a sold house in the Sierra foothills with a dual-axle 14' U-Haul, packed full. Towed like it wasn't even there. Likewise road trips from SoCal to Albuquerque were good at 16mpg cruising down the highway. Getting around 14.5mpg commuting in L.A. Put 130k+ on the '99 and over 144k on the '05 now and it's still going strong, not leaking a drop. Water pump is the only thing we've had to do to it, aside from regular maintenance.

I too had set my sights on a K2500 suburban as my 'project' vehicle, using much the same criteria as you've expressed. I was sure I wanted the heavier duty brakes and the 4L80 trans. But I had some trouble finding any that didn't have the big fuel-sucking motors (8.1/454). But ultimately I just recently purchased an '02 K1500 LTZ Suburban with all the options and comparatively low mileage of 116k, overall in great shape for $5300. And it too has the 5.3L. I'm happy to have it. I've just finished doing the equivalent to a 100k mi service to it and I think it will do all I ask of it, which is pretty much the same as your criteria.

To the poster worried about the size / parking, the Suburban is almost exactly the same wheelbase and overall dimensions as a full-size longbed pickup. I've been daily-driving and parking one of those for ~28yrs 360k mi. It isn't that difficult.

Looks a little silly having His & Hers SUVs, but you can see all three in this pic -

In closing to the OP, consider the 1500-class. There are some out there with the 6.0L as well.

What gear ratio are you running in the axles the 4.10 or 3.73?

 

[rayra]

3.73 in everything, if I'm not mistaken, that's the default / standard, particularly with the overdrive trans. I think you have to special order 4.10s on the 1/2 ton trucks. The Z-71 package includes the G80 Locker axle package. They also have a 'tow' button which basically locks out 4th gear eta - does a lot more than that, changes shift points too.
The pickup usually has 31x10.50x15s on it, and the Z71s wear 265/70-17s which are also essentially 31s.

The higher gearing would help if you are towing a lot, but in conjunction with the bigger motors your fuel economy will really suck. Be lucky to see 9mpg with the 454. We're getting a solid 14+ around town. Over 16 cruising in the low 70s. I don't recall what our towing mileage has been overall. Don't do it often.

 

[Kaisen]

4.10s were standard in the Z71 trim, as pictured above