Chevrolet Suburban 3500 Questions

[Doubeleive]

Marky, you seem to be asking the questions right before I get to them! I was looking online last night for new hitch units and there are none online that are made for the 3500 Suburban. I will have to upgrade it, but may need to go to the local trailer dealer and have them take a crack at it. I have been analyzing DuraburbInc’s YouTube video showing a frame tear down. I cannot tell if this is an upgraded previous gen 2500 suburban chassis or if it’s the shared chassis from the Silverado 3500.

you might try reaching out to draw-tite they only list one for a 3500 silverado but I bet they have taken measurements for a 3500 suv I used to know a guy that worked for them and his only job was to go around and measure every new vehicle so they could design a hitch

 

[Bigburb3500]

I've spent a decent amount of time in the past analyzing what the true towing capability would be for my 2010 GMC Yukon XL 2500. I went component by component trying to see what the differences were between what was in the Yukon vs what is in the 2500/3500 GM trucks of similar vintage - and comparing the rated tow capabilities out of the GM brochures.

I think you could take a similar approach to your 2018 3500.

For instance, somewhere on Youtube is video by the guy at Duraburb about the frame used under the 3500 Suburban. He basically says: it's the same exact frame that is under the 2007-2013 2500 Yukon XL/Suburbans and the earlier generation 2500 Yukon XL/Suburbans.

The 2000-2006 2500 Suburbans had the 8.1L big block engine option - and with the right gear ratio - that truck was rated to tow 12,000 pounds. So the way I look at it is: that frame is rated to tow 12,000 pounds (at least). - with the right hitch on it.

Now look at the brakes - you can figure this out by going part number by part number and seeing what brakes are on the 2500/3500 trucks vs what is on the 3500 Suburban. I would be willing to bet that there is no difference there - so your truck's brakes are going to be good for whatever tow rating that the comparable year 2500/3500 pickups are good for.

I think the 2500/3500 gas pickups have the 6.0L engine. So look at the tow ratings in the GM brochures are for that engine - in combination with the gear ratio. If you look at the brochures they'll give the tow ratings by engine/gear ratio - and body style. The heavier body styles - have a slightly lower tow rating. Compare those weights against whatever the listed weight is of your 3500 Suburban - and you can probably get a pretty good estimate of what a "factory" tow rating would be for your truck if it wasn't designed to be up-armored.

I would also bear in mind that - you can enhance the tow rating by upgrading components. For instance: I installed a set of the Wilwood huge brakes on my truck because at one point I was commuting with it in rush hour traffic and almost rear ended people a few times.

If I had to take a wild guess - I can't see the towing capability of your truck being any less than the previous generation 2500 Yukon XL/Suburbans - which is like 9700 pounds.

Calsdad,
I have rewatched Duraburb’s video several times and maybe I need to watch it a few more. I am going through exactly what you recommend by checking parts and comparing them to the HD pickups. I need to more closely analyze the frame section because I felt he glossed over the differences. I forget what part he was commenting on and then he said “And that’s how they get the 1ton rating.” I know ratings are based on a number of different factors but I did think the frames from 2500 to 3500 would also be different based on metal thickness.
You make a great point about using a 2500 previous-gen as a base line and going from there. The brakes on this 3500 are right off a 3500HD and same with cooling for trans and oil. The rear leafs are also 3500 not 2500 so I think we are probably past the 10k mark? How far past would be a crap-shoot. Looking at a comparable 3500 it looks like the GVWR is about 10500-10700 and the sticker on my Burb is 11k.

Your methodology is great! Thank you for the input. Do you tow with yours much and have anything you would change/recommend?

Cheers.

 

[Bigburb3500]

you might try reaching out to draw-tite they only list one for a 3500 silverado but I bet they have taken measurements for a 3500 suv I used to know a guy that worked for them and his only job was to go around and measure every new vehicle so they could design a hitch

I am going to reach out to them or there is a local hitch/trailer shop that I might talk to them and see what options they provide.

I’m no custom metal fabricator, so if one of these two places can point me towards a product that works I can run a few bolts.

Really appreciate the responses.

 

[calsdad]

Calsdad,
I have rewatched Duraburb’s video several times and maybe I need to watch it a few more. I am going through exactly what you recommend by checking parts and comparing them to the HD pickups. I need to more closely analyze the frame section because I felt he glossed over the differences. I forget what part he was commenting on and then he said “And that’s how they get the 1ton rating.” I know ratings are based on a number of different factors but I did think the frames from 2500 to 3500 would also be different based on metal thickness.
You make a great point about using a 2500 previous-gen as a base line and going from there. The brakes on this 3500 are right off a 3500HD and same with cooling for trans and oil. The rear leafs are also 3500 not 2500 so I think we are probably past the 10k mark? How far past would be a crap-shoot. Looking at a comparable 3500 it looks like the GVWR is about 10500-10700 and the sticker on my Burb is 11k.

Your methodology is great! Thank you for the input. Do you tow with yours much and have anything you would change/recommend?

Cheers.

I don't think there is any difference between the frames in the 2500 and 3500 pickups. You could probably figure that out by checking some of the online GM parts sites - if I remember correctly they have the entire frame listed in there somewhere. It's been a few years since I did it, but my belief is that the difference between the 2500 and 3500 trucks pretty much came down to the rear springs. I don't recall there being any other differences that I could find when I looked at all the part numbers.

I'd have go back and find that Duraburb video again - but the 2500 series SUVs ended when the GMT900's ended in 2013. By then - the pickups had already converted over to the "metric" wheel lug bolt pattern. But the SUVs stayed with the "old" pattern. I think the 3500 SUV like what you have - uses the new metric bolt pattern and may use the new pattern front suspension from the equal-year HD trucks. I don't recall there being any big differences that Duraburb pointed out on the frames other than that.

One thing to bear in mind is - the 3500 SUV was a short run vehicle - GM would not have spent much $$ trying to develop a new frame or anything else for it - they part-binned it as much as possible.

 

[Thrust]

https://gmauthority.com/blog/2017/07/chevy-suburban-3500hd-heavy-duty-vs-chevrolet-suburban/

 

[Bigburb3500]

https://gmauthority.com/blog/2017/07/chevy-suburban-3500hd-heavy-duty-vs-chevrolet-suburban/

Thank your Thrust for the link! The 6585 curb weight makes a good bit of sense and I think lines up with its 1ton underpinning. Still funny how this blog says it comes with all the heavy duty tow adds but that hurts its towing capacity
Do we think anyone writes an article like this and says to themself, “ Yes, I’m making sense today.”

 

[15burban]

Just a guess, but since they didn't make very many of them and only sold them new to fleet customers for "upfitting." Gm probably didn't bother going through the j2807 towing tests to determine an actual gcwr for them. They probably just used the regular (1500) suburban gcwr hence the high payload but really low towing capacity.

 

[mikeyss]

I remember the older GMT900 2500 suburbans had a mechanical cooling fan, but I remember seeing a picture of the 3500 Suburban using electric cooling fans. Is this true, or was it a picture showing a normal Suburban?
Also, do the 3500 have beefier torsion bars? I *think* some have the 9.5" 14 bolt rear ring and pinion, and some have the 10.5 14 bolt.

 

[Doubeleive]

Thank your Thrust for the link! The 6585 curb weight makes a good bit of sense and I think lines up with its 1ton underpinning. Still funny how this blog says it comes with all the heavy duty tow adds but that hurts its towing capacity
Do we think anyone writes an article like this and says to themself, “ Yes, I’m making sense today.”

i put that thing on a cat scale and see what it weighs

 

[calsdad]

Just a guess, but since they didn't make very many of them and only sold them new to fleet customers for "upfitting." Gm probably didn't bother going through the j2807 towing tests to determine an actual gcwr for them. They probably just used the regular (1500) suburban gcwr hence the high payload but really low towing capacity.

That actually makes sense - because the tow rating they give for the truck doesn't really add up based on the components they used to put that truck together. For instance, I have the GM brochure for the 2015 HD trucks saved on my computer - and the GCWR (combined weight rating) for a crew cab pickup with the Vortec 6.0L V8 gas , with a 4.10 gear ratio - is: 20,500 pounds. That 3500 Suburban has the same drivetrain and has the 4.10 gear ratio if I remember correctly - so it should have a similar GCWR. Only having a 3500 or whatever it is pound tow rating just makes no sense at all.

I'd have to go back and start digging thru the GM brochures to find it , but GM at one point was selling the HD trucks with either the 3.73 or 4.10 gear ratios available - and 4.10 trucks had a sizeable increase in tow capacity rating over the 3.73.

 

[calsdad]

Just a guess, but since they didn't make very many of them and only sold them new to fleet customers for "upfitting." Gm probably didn't bother going through the j2807 towing tests to determine an actual gcwr for them. They probably just used the regular (1500) suburban gcwr hence the high payload but really low towing capacity.

Bingo - that makes total sense.

I did some searching for GM literature to see what the GCWR is for the "standard" 2017 Suburban - and found the Chevrolet 2017 Towing and Trailering guide:

Site Maintenance

In section 13, Colorado , Tahoe , Suburban , etc - it says that the Tahoe/Suburban with the EcoTec 5.3: V8 with Max Trailering Package - has a GCWR of 14,000 pounds.

So with the GVWR of the Suburban 3500 being 11,000 pounds - that gives you the 3000 pound tow rating.

 

[Bigburb3500]

I remember the older GMT900 2500 suburbans had a mechanical cooling fan, but I remember seeing a picture of the 3500 Suburban using electric cooling fans. Is this true, or was it a picture showing a normal Suburban?
Also, do the 3500 have beefier torsion bars? I *think* some have the 9.5" 14 bolt rear ring and pinion, and some have the 10.5 14 bolt.

It has the electric cooling fans and has the 10.5” rear end with 4.10. She’s beefy. Not sure about the torsion bars.

 

[Bigburb3500]

That actually makes sense - because the tow rating they give for the truck doesn't really add up based on the components they used to put that truck together. For instance, I have the GM brochure for the 2015 HD trucks saved on my computer - and the GCWR (combined weight rating) for a crew cab pickup with the Vortec 6.0L V8 gas , with a 4.10 gear ratio - is: 20,500 pounds. That 3500 Suburban has the same drivetrain and has the 4.10 gear ratio if I remember correctly - so it should have a similar GCWR. Only having a 3500 or whatever it is pound tow rating just makes no sense at all.

I'd have to go back and start digging thru the GM brochures to find it , but GM at one point was selling the HD trucks with either the 3.73 or 4.10 gear ratios available - and 4.10 trucks had a sizeable increase in tow capacity rating over the 3.73.

I agree 100% - this was not a truck designed to tow, but rather “haul” stuff around. Armor or large command center style items.
But seeing as I do not live in “that part of town” and do not been be overly concerned I am more interested in the towing.

I think generally speaking we are all coming to the same conclusion: Without any upfit packages this is pretty similar to a comparable 3500. It seems the largest limiting factor is the hitch at this point, and getting the truck to a scale would be helpful.

 

[calsdad]

According to the Chevrolet 2003 brochure for the Suburban, the 2500 with the 8.1L Vortec, 4.10 gear ratio had a GCWR of 19000 pounds and a max trailer weight of 12,000 pounds. The 8100 V8 gas was rated at 340hp @ 4200 rpm with 455 lb ft of torque.

I'd have to go lookup what a 2500/3500 pickup with the L96 6.0L and a 4.10 gear ratio is rated at for towing to get a more precise idea of what your 3500 Suburban should be capable of towing. But the above numbers from the 2003 should give you some idea.

Bare minimum I think what you're looking at is at least 10K in towing capability.

 

[Bigburb3500]

Bingo - that makes total sense.

I did some searching for GM literature to see what the GCWR is for the "standard" 2017 Suburban - and found the Chevrolet 2017 Towing and Trailering guide:

Site Maintenance

In section 13, Colorado , Tahoe , Suburban , etc - it says that the Tahoe/Suburban with the EcoTec 5.3: V8 with Max Trailering Package - has a GCWR of 14,000 pounds.

So with the GVWR of the Suburban 3500 being 11,000 pounds - that gives you the 3000 pound tow rating.

I am not sure I follow you here. GVWR is different than GCWR. I found this for a 2018 Suburban LT on MotorTrend, GVWR is only 7500lbs. A comparable Silverado 3500 has a GVWR of 10700-12000. KBB shows it at 11600. I think @Doubeleive is right, to really figure out some of these figures a true Cat-weight will help a lot. In the end this truck seems to be lining up pretty close to the Silverado 3500, but was expected to has upfit packages on it not tow 30ft campers/boats.

https://www.motortrend.com/cars/chevrolet/suburban/2018/specs/

https://www.kbb.com/chevrolet/silverado-3500/2018/

 

[Bigburb3500]

According to the Chevrolet 2003 brochure for the Suburban, the 2500 with the 8.1L Vortec, 4.10 gear ratio had a GCWR of 19000 pounds and a max trailer weight of 12,000 pounds. The 8100 V8 gas was rated at 340hp @ 4200 rpm with 455 lb ft of torque.

I'd have to go lookup what a 2500/3500 pickup with the L96 6.0L and a 4.10 gear ratio is rated at for towing to get a more precise idea of what your 3500 Suburban should be capable of towing. But the above numbers from the 2003 should give you some idea.

Bare minimum I think what you're looking at is at least 10K in towing capability.

It makes 360hp and 380ftlbs per the spec sheet. The 3500 Silverado’s rating is 13k-14klbs towing.

I really appreciate you chiming in on my thread. I think the hitch is the major limiting factor and I found a place that will either order a higher rated hitch or will custom fabricate one to ensure it can hold whatever I hang off the bumper.

 

[calsdad]

I am not sure I follow you here. GVWR is different than GCWR. I found this for a 2018 Suburban LT on MotorTrend, GVWR is only 7500lbs. A comparable Silverado 3500 has a GVWR of 10700-12000. KBB shows it at 11600. I think @Doubeleive is right, to really figure out some of these figures a true Cat-weight will help a lot. In the end this truck seems to be lining up pretty close to the Silverado 3500, but was expected to has upfit packages on it not tow 30ft campers/boats.

https://www.motortrend.com/cars/chevrolet/suburban/2018/specs/

https://www.kbb.com/chevrolet/silverado-3500/2018/

The Chevrolet towing document I referenced - gave a GCWR for the 2017 Suburban as being 14,000 pounds. Your 3500 Suburban has a GVWR of 11,000 pounds - ergo ..... what's leftover from that 14,000 lb GCWR - is 3000 pounds - which is how you end up with the 3000 pound FACTORY tow rating for your 3500.

Basically it sounds like GM punted on coming up with an actual tow rating for the 3500 Suburban - likely because whatever spec came down from .gov for what they needed out of a Suburban that can be up-armored - had no requirements for an actual tow rating. So - as 15Burban said: they likely didn't bother running the tow rating tests and since the "regular" Suburban is already certified to have the 14,000 lb GCWR - and the 3500 Suburban has a rated 11,000 lb GVWR - you've got 3000 pounds of extra capacity to do something with - so they just throw that under tow rating.

Honestly I think people are taking the factory ratings on the 3500 too "seriously". Like I said before - look at the components used in the truck and look at what they're rated for in other trucks the very same components get used in - by going thru that you can come up with a realistic rating of what the 3500 is going to be capable of towing.

For example: (from the GM brochure for 2010 Silverado)
L96 6.0L engine with 4.10 gearing in a 2010 Silverado 3500HD SRW Crew Cab 2WD with 8ft box: Max trailer weight 12,200 lbs

2003 Suburban with the 8.1L gas V8 and a 4.10 rear end ratio tow rating is 12,000 pounds.

Now you've got a FACTORY rated tow rating on the exact same drivetrain that is your truck of 12,200 pounds , and a FACTORY tow rating for pretty much the exact same frame that is in your truck of 12,000 pounds - ergo - your truck should have a realistic tow capability of right around 12,000 pounds.

 

[Doubeleive]

yep i would fill up the tank, hell it might have 2 or the reserve anyway, then get a front axle, whole truck and rear axle weight and go from there. with the 4.10 it "should" be able to tow more than a 3.73, presuming its not heavy as hell. if it's not upfitted I don't see what adds 3500 lbs to a stock truck

 

[15burban]

What do you plan on towing? Sorry if I missed it. Also some hitches have a higher rating when using a weight distribution hitch. Just a quick look on etrailer the first replacement hitch for my truck says 10k max but also 12k max with a weight distribution hitch.

 

[calsdad]

I looked thru all of the GM Suburban and Yukon XL brochure PDF's I have saved - and none of them seemed to list a curb weight.

So I went and did a google search - and it says the curb weight for a 2010 Suburban 2500 is 6215 to 6551 pounds.

It says a 2010 Suburban 1500 is 5846 to 6024 pounds.

So it looks like the difference between the 2010 Suburban models is 369 to 527 pounds.

You could probably just round this off to 500 pounds difference for sake of simplicity.

A search for the 2018 Suburban curb weight says it's 5808 pounds. So not really much difference between a 2010 and a 2018

Since the engine, transmission, rear axle, and the frame are pretty much exactly the same between the 2010 Suburban 2500 and the 2018 Suburban 3500 - just add 500 pounds to GM's listed curb weight for the 2018 "1500" Suburban and that should put you pretty damn close to what the actual curb weight is for the 2018 3500.