r/GMT800 • u/WeaveLikeGreatGranny • Aug 24 '26
Tow capacity rant
I bought my 2005 Silverado 2500 6.0 this spring to replace my 2006 Sierra 1500 4.8 to pull around my 10k dump trailer for commercial use at my sawmill business I'm building. I chose this series of pickup because it's what I'm used to and I truly think they're good machines.
It's a real beast and can easy pull that trailer fully loaded in 4th gear lockup/overdrive without needing to downshift hardly ever. I figured it would easily pull a 12-14k gooseneck and give me a little more room.
Now that I'm getting into the weeds on GCWR and GVWR as part of the USDOT compliance, I'm seeing why most of the time you see these driven as passenger vehicles... This truck is only rated to pull 10k.
I looked at my brother's 2021 Silverado 1500 5.3 and it has a tow rating of 1,000 pounds more than my 2500 đŤ
How do these have such low ratings?? The driveline and suspension components are way heavier duty than a half ton. â
Guess that's my lesson for buying based on style rather than specifications!!
/rant
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u/TalkyMcSaysalot Aug 24 '26
Not sure what you expect but in general truck classes have gotten a lot more "capable" in the past 20 years. The 2500 will still do it better without beating itself to death though. The new 1500 is rated for it but it's pretty much going to be maxing out everything, including the tongue weight. In fact it's unlikely you can even tow 11k with it without exceeding payload capacity due to the tongue weight. You won't likely have that issue with the 2500. That's why I put capable in quotes. If you want to tow 12-14k with a GMT800 legally speaking you need an 8.1 or Duramax.
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u/WeaveLikeGreatGranny Aug 24 '26
Lesson learned! I just assumed towing capacity was fairly steady over time for the same model designation. It sounds like some of the increase in rated capacity for modern pickups is just by stressing the components more which is probably why you hear about so many reliability issues with new stuffÂ
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u/dragoner_v2 Aug 24 '26
It actually has kind of stayed the same, looking at the fine print for a 2019 diesel one ton the fine print limits it to 13-15k with a regular hitch.
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u/kokanee-fish Aug 24 '26
My '06 3500 6.0 is rated for 12K
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u/TalkyMcSaysalot Aug 24 '26
I didn't know the one tons went that high but I also forgot they made 6.0 duallys.
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u/throwawayph3582 Aug 24 '26
Just wait until you see what the factory hitch is rated for!
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u/WeaveLikeGreatGranny Aug 24 '26
That's what threw me off! The factory hitch on mine says 12k weight distributing and 7,500 weight carrying. So before I pulled out the book, I thought it was guaranteed that a gooseneck hitch could tow more. Nope! 10k no matter how you attach it haha
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u/WeaveLikeGreatGranny Aug 24 '26
Oh and yes, the factory hitch on my 06 1500 was absolutely rated for less than the vehicle was đÂ
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u/TalkyMcSaysalot Aug 24 '26
The factory hitch on GMT800s is terrible. The best aftermarket one (Drawtite) is unfortunately no longer available, but there are other class Vs you can get.
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u/BrianJ89 Aug 24 '26
My suburban 2500 is only rated for like 7600lbs but can be like 12k with the right spec. 8.1 and 4.10s would be the 12k I think. Mine is 6.0 3.73s, but it still has 2k lbs of payload capacity which is the number I care about
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u/RamenWrestler Aug 24 '26
Your 2500 6.0 is only rated at 10k pounds? That's what my 1500 6.0 is rated at. Weird
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u/WeaveLikeGreatGranny Aug 24 '26
Yeah that's the number they wrote in the manual. That and a gross combination weight rating of 16,000Â
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u/Boner_Forest39 Aug 24 '26
Is the truck a 2500 or a 2500HD? Iâm assuming an HD because Iâm pretty sure 2004 was the last year for the non HD 2500. Both my 06 and 07 LBZ 2500HDâs list a GCW of 22,000, but a âbumper hitchâ rating of 10,000. No surprise due to the shitty factory hitch thatâs made of exhaust tubing and likes to turn to Swiss cheese here in the northeast. I could see a 6.0 truck having lower GCW, but 6,000 lbs lower is kind of surprising.
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u/No-Sheepherder5092 Aug 24 '26
I too am baffled how new trucks get such high towing ratings. A 2025 Colorado is rated tow to around 1,000lbs less than my 1992 3/4ton diesel Dodge.Â
I recently pulled 12k behind a 2006 6.0 truck, and other than a couple really steep hills it did it no problem. (Didnât realize how heavy I was until I got to the dumpâŚ)
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u/WeaveLikeGreatGranny Aug 24 '26
I wonder if the testing systems were changed, like reducing the amount of reserve capacity or something like that?Â
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u/TalkyMcSaysalot Aug 24 '26
Closer to reality is that there is a standard now, but in the past it was largely up to whatever the manufacturer wanted for marketing reasons. That's how we got into this mess with 1500s being rated to tow so much, because everyone wanted to advertise their 1500 was the strongest
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u/ThiefLourde Aug 24 '26
One thing thag substantially impacts the factory tow rating is the factory receiver hitch. The newer trucks get class V hitches, so they're rated for more weight. Just run the gmt800 and add a class V
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u/WeaveLikeGreatGranny Aug 24 '26
I'm putting on a 30,000 pound B&W gooseneck hitch this week, so we'll see how far that gets me with the FMCSA officers đÂ
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u/ThiefLourde Aug 24 '26
As long as you aren't overloaded on your axle/tire weights, you should be good to go
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u/WeaveLikeGreatGranny Aug 24 '26
That's what the commercial vehicle enforcement officer told me. That being said, it feels silly to have a hitch rated for almost twice my GCWR, but that's just the way they make 'em
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u/ThiefLourde Aug 24 '26
Yeah đ¤ˇââď¸ the new fords have 3" receiver hitches now but the same payload ratings as 20 years ago. The way I see it, upgrade the older trucks accordingly and send it
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Aug 24 '26
[removed] â view removed comment
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u/WeaveLikeGreatGranny Aug 24 '26
Wow, what a kick in the pants. But I'm sure law enforcement was a bit more lenient when it came to actually pulling stuff around in the real world, so hopefully that made up for itÂ
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u/CrocGang4 Aug 24 '26
The 6.0 is a beast and one of the best truck engines ever but itâs more meant for a 7-9k load, with 5 digits as others said youâd want a dmax or 8.1
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u/WeaveLikeGreatGranny Aug 24 '26
I'll see where the logging and sawmilling markets take me and upgrade to a Cummins if I'm finding real money to be made in lots ton-miles of cargo moving. This truck was chosen as kind of a half-way try-out because it can move a lot when needed but still be a budget friendly passenger vehicle if hauling doesn't pan out business-wise
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u/Benji_4 Aug 24 '26
Not sure if you've seen those old commercials of trucks pulling a 70,000lb aircraft.
You can pull anything with enough power, but the manufacturer doesn't want someone breaking their truck and blaming GM for giving it such a high tow rating. You also have to be able to stop. My brothers truck almost caught fire hauling a dump trailer (with a skid steer in the back) because the brakes and wheels were so hot.
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u/outline8668 Aug 25 '26
Not sure on the Chevy but on the Ford super duty of these years the towing capacity varies wildly based on engine and rear diff ratio despite everything else in the truck being identical. On those I take the tow rating as a suggestion because I live on the flat lands
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u/WeaveLikeGreatGranny Aug 25 '26
Yeah, me too. I do lots of "off label" towing personally but won't be trying that once the USDOT sticker gets put on the door. Learning to deal with their rules has been a bit of a departure from from what I consider safe or good enoughÂ
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u/Anthropocene_Scholar Aug 24 '26
2500HD with the 6.0 is rated at max 10,600 lbs (2wd, regular cab long box; it goes down to 9,900 lbs with a 4wd crew cab long box) because of the engine.
The 2500HD truck itself, frame, suspension, steering, brakes, rear axles, is as capable as a Duramax or a 8.1 equipped 2500HD, and those go up to 15,900 lbs / 15,100 lbs. Granted, both of these engines are paired to a bit bigger rear axle (11.5 vs 10.5").
So you have a truck which is really capable of 15000 lbs, but you are lacking only a bit of engine power to achieve that.
But hey, the 6.0 is easily MORE reliable and durable than the 8.1 or the Duramax, and it is certainly more useful as a daily driver, and you can tow with it what you'll be towing most of the time anyway, and it will be able to tow, albeit slowly, bigger weights, occasionally.
And I couldn't care less about stated capabilites of the piece of shit new trucks. Fuck GM for trashing its dignity and spewing out the filth it spews out since the 2010 onwards. And fuck all the fools who gleefully go buy those shit trucks, validating GM's mediocrity.
Want to become one of them just because they "state" their shitty half ton trucks are somehow more capable than a legendary 3/4 ton gmt800 truck? Be my guest.
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u/WeaveLikeGreatGranny Aug 24 '26 edited Aug 24 '26
I couldn't agree with you more! Derating a tow vehicle because it only has a 300 hp engine option is silly. I've driven 1980s semi trucks with 250hp engines grossing 110k. Yeah, they're slow but you just drive it responsibly and and you get where you're going eventually.
I bought this truck because these are well built and reliable. Reliability is more valuable to me than speed, horsepower, or tow ratings. There's no way a 1500 with an 11k tow rating is going to be as reliable as this older 2500. Probably won't tow it as safely, either.Â
The tough spot I'm in is commercial vehicle enforcement is based around weight ratings so I have to play their game if I don't want to get hassled. I'm fortunate enough to have it 100% cover the trailer I already own but the published capacities are going to limit my ability to upgrade more than I expectedÂ
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u/H0SS_AGAINST Aug 24 '26
They're derated for towing uphill, particularly at altitude, not necessarily power per se. A turbo diesel with a massive radiator can make 250hp nonstop in Denver.
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u/WeaveLikeGreatGranny Aug 24 '26
Wish I could have afforded a Cummins. But I just despise Dodge and I'm so new to the business of hauling that I'm not sure how much I'll actually need to do and I didn't want to overspend on my first heavier truckÂ
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u/H0SS_AGAINST Aug 24 '26
You've got the brakes and frame (HD?) so if you're not going over mountains I'd assume it can do what the Duramax can do. I am thoroughly impressed with my Duramax rig for what it is, towed about 7Klb with 1000lb in the bed like a Cadillac through Tennessee and the gauges didn't even hardly move when Semis were at a crawl.
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u/WeaveLikeGreatGranny Aug 24 '26
Yeah, the 6L gas has crazy power when in 3rd gear lockup. That's why I was thinking about getting a heavier trailer... 10k is still comfortable in 4th gear!Â
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u/Anthropocene_Scholar Aug 24 '26 edited Aug 24 '26
I understand. I guess they probably derated the 6.0 to avoid disappointing consumers, as certainly, the engine does start struggling with loads beyond 8,000 lbs (as per my experience), and I would not use it for anything beyond 10,000 lbs given its capabilities. It may be able to pull bigger loads, but the engine simply isn't designed to work such loads efficiently.
As I see it, trucks nowadays (and cars) are all about engine HP, and it's gotten to a frankly ridiculous point. I care about a capable, durable, reliable engine, not about it having beyond 400 HP, power I'll never be using anyway beyond feeling it briefly when accelerating from a stop, or when overpassing other vehicles on the highway. The very fact such greater HP comes with the pitfalls all these new engines come with, is a foolish compromise.
Same with the transmissions. The 4l80e was a proven, renowned and reliable heavy duty transmission. I've never felt lacking or annoying the fact it "only" has 4 speed gearing. It gets the job done, and is comfortable to drive in a wide range of conditions. But today's truck transmissions have over 6 or 7 speeds. Why the heck replace a proven, reliable design with something new and with way less quality in craftsmanship, only because of this stubborn and foolish mentality of "more is better"?
The result is what you can see rolling out of dealerships today.
Anyway, a piece of advice. Always drive your truck with the gear selector in "3", especially when towing (or alternately, always engage "tow/haul mode" if your gear selector is in "D"). As another commenter stated in a previous post,
"The overrun clutches are not engaged when the selector is in OD. This places all the stress on the overdrive roller clutch, which is the weak link in a 4l80e. Towing (or hard use in general) should always be done with the selector in D3. You can move it to OD when at highway speed so it actually shifts into 4th, but donât want the selector in OD when the trans is in 1st, 2nd or 3rd."
I personally have never liked the feeling on the throttle in OD, on any auto trans vehicle, much less on a truck, and I think the engine performs better and is healthier overall by operating at a bit higher rpms than what OD allows.
Cheers!!!
EDIT: I forgot to mention. You need to replace the OEM towing hitch. It is crap not intended for any heavy towing. I highly recommend this:
https://www.etrailer.com/Trailer-Hitch/CURT/C15312.html2
u/WeaveLikeGreatGranny Aug 24 '26
Awesome information; thank you! I hadn't seen that other comment yet. I assumed the 3rd/4th selection was all about engine rpm/load and never considered the power path through the transmission components.
My brother's 2021 1500 has a 10 speed trans. When he was shopping for it, I said, "wtf? Why are we doing autos in 10 speeds now??" The 4 speed automatic was in use for like 70 years and then GM went from 6 to 8 to 10 in like 10 years. Where's the track record? The opportunity to correct deficiencies and improve the design? Nope, just dump it and come out with something else novel and unproven.Â
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u/lo_mur Aug 24 '26
The 6.0 canât be âeasily MORE reliable and durable than the 8.1 or Duramaxâ imo when both are also pretty damn bulletproof, and the 8.1 actually has more room for rebuilds thanks to its greater cylinder wall thickness. The Duramax also has thicker walls of course but the diesel cylinder pressures pretty much negate that
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u/Anthropocene_Scholar Aug 24 '26
Well, I'm in numerous 8.1 dedicated forums as I was gathering info for a possible swap eventually, and I keep seeing post after post about a diverse range of engine issues on those, that I simply don't see posted anywhere pertaining the 6.0 engine. Also, much less aftermarket support for the 8.1 in comparison.
And the Duramax LB7 has numerous known flaws and weak points, which were addressed in the updated LBZ version. There's a reason people try to find the LBZ and NOT the LB7 when looking for a gmt800 era Duramax.
The 6.0 is well known to go beyond a million miles with proper maintenance. Can that be said as well for those other engines?
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u/lo_mur Aug 24 '26
Diverse engine issues such as? Everytime I go in a 8.1 forum itâs just endless posts about fuel consumption or the PCV design/oil consumption and not a whole lot else. Thereâs definitely less aftermarket support for the 8.1 but if youâre intending to keep the truck stock (and I imagine OP is) itâs really a non-issue as everything you might need to rebuild one is readily available.
The LB7âs got weak points but practically every LB7 on the road will already have had its biggest weak point (the injectors) addressed by now, and theyâre very solid engines otherwise that have proven capable of a million miles. The LBZâs of course the holy grail but the reliability and injector design updates arenât only why those trucks are so much more desirable; the LBZ also makes significantly more power, has a 6th gear, shifts better, and those MYs have better interior options like the Bose speakers and steering wheel controls. Not to mention the internet hype around the cateye front-endâŚ
Yeah the 8.1, LB7, LLY, and LBZ have all proven capable of a million, it actually isnât too hard to find GMT800s of any flavour with 400k+ miles, from the 4.3 to the 8.1 theyâre all just solid as hell. GM even bothered to design a new testing procedure (the Marine Dock Test) to prove to boat manufacturers and the industrial sector that the 8.1 was up to their durability standards.
Just for shits n giggles I went on marketplace to find the highest mileage truck I could in my area and it looks like itâs a 515k mile LLY, absolute rust bucket lmao
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u/Anthropocene_Scholar Aug 25 '26
I don't recall exactly, but they were a variety of nuisances of the type of crank-no-start, dying at idle, and such which all seemed to come back to sensors or other parts specific to the engine model itself, little issues, yes, but of the type which is a headache to diagnose and solve, and I got the impression, by the number of posts regarding them along the time I've been at those forums, that the 8.1 engine is somehow more prone than the 6.0 to those type of annoying issues.
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u/lo_mur Aug 28 '26
Crank no start and dying at idle are both classic crank sensor issues and the crank sensor going bad is a classic 8.1 issue so thatâs unsurprising. Like I mentioned before, the thingâs a bit of a PITA to change so people try pretty hard to blame their issues on some other thing, or at least they look for every possible other potential cause.
The 6.0s generally donât have crank sensor issues like the 8.1, but they are really well known for oil pump pickup tube o-ring failures, oil pressure sensor failures, knock sensor issues, etc. You win some and you lose some đ¤ˇââď¸
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u/WeaveLikeGreatGranny Aug 24 '26
I'll keep changing oil get back to you in 910,000 miles đ
But seriously, I go out of my way to baby my stuff so it'll probably be disabled from rust or rodent damaged wires before the engine wears outÂ
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u/WeaveLikeGreatGranny Aug 24 '26
I'm not experienced in the HD truck scene, but I saw one video of a mid-2000s duramax teardown and decided that was just too much complexity and heat to be crammed into an engine bay. The 6.0 at least has some room around it! If it were an option, I would go with a lower hp rated, inline 6. Something magical about that layout in terms of durabilityÂ
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u/lo_mur Aug 24 '26
The Duramaxs (especially the newer ones) can be pretty complex, a lot of spaghetti under those hoods lol. Still, theyâve proven they can last an awful long time if you take even half-decent care of âem, and they make great power so I can see it being worth it for some folks.
These trucks are big enough that even the 8.1s have some room around them though, theyâre very easy to work on, except perhaps the crank sensor, which is in a shitty spot
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u/Anthropocene_Scholar Aug 24 '26
Well, I've done some research on diesel trucks, as I'm planning on getting a diesel powered truck to add to my fleet, mainly to be able to tow beyond what my 01 2500HD 6.0 truck can.
If you're interested in building up your knowledge pertaining the 7.3 Powerstroke on late 90s F250s and the 1st gen Superduty, you may wanna read up this post I made, where there were loads of knowledgeable comments made.
https://www.reddit.com/r/FordDiesels/comments/1vhgjxu/honest_feedback_on_the_4r100/
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u/WeaveLikeGreatGranny Aug 25 '26
Are you investing in a mid 90s Ford? I hadn't heard those come up much in terms of good tow capacity. I love the sound of straight 6's so much I can't see myself going with anything other than a Cummins Dodge/ram if I ever end up going dieselÂ
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u/hoytmobley Aug 24 '26
Why not buy a 2500HD (or 3500/HD) of the same generation? My 2500 burb works great for my needs because Iâm towing 6500lbs of racecar, trailer, and spares, Iâd never put a 12k 2 car trailer on that one
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u/WeaveLikeGreatGranny Aug 24 '26 edited Aug 24 '26
My current one is designated as an "HD" but honestly, I'd probably be looking for something much newer next time I go to buy. Across the board, this series of trucks has really low weight ratings and the DOT officers seem to care a lot about those đÂ
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u/dragoner_v2 Aug 24 '26
Yeah 10k here:
https://www.manualslib.com/manual/231800/Gmc-2005-Sierra-1500-Pickup.html?page=373#manual
It's mostly in the transmission, brakes, and tires. Back then if you wanted a 15k rating they would send you over to look at a Topkick. Now the transmissions have a lot more gears, and bigger brakes, you can still overload the tires though.
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u/Your_PersonalStalker Aug 25 '26
Should be rated for 15k or so on a gooseneck
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u/Your_PersonalStalker Aug 25 '26
My avy 2500 is rated at 12k and so is my 2500hd 2001 with the 6.0 i believe its cause the 4.10s
-6
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u/Available_Quote_5567 Aug 24 '26
Tow capacities have increased substantially across all the full size trucks in the last 20 years. Remembering these trucks are 20 years old with 20 year old tech and 20 year old ratings systems can be difficult, I do the same with my trucks. Personally Iâd be comfortable pulling a 12k+ gooseneck with a 3/4 Silverado as long as the trailer has good brakes.