Towing capacity?

Hello TWEBB101,

Is it a 2 door, 4 door bonus cab, or a 4 door crew cab?

By the way, awesome truck, I am jealous lol.

Thank you,
Brendon
2CarPros

Thank you! It was my Grandpa's pickup. glad I get to keep it going. It's a 2-door.

Hello TWEBB101,

You're welcome! Let me take a look and see what I can find for you.

Thank you,
Brendon
2CarPros

Hello TWEBB101,

Well, I called 3 different GM dealers in 3 different states, and nobody could give me any information. That's what I thought but figured I would try anyway. But I did find some interesting information.

Gross vehicle weight rating (GVWR) is the maximum amount a vehicle can weigh as it rolls down the road. This number includes the curb weight of the vehicle, all occupants, and all cargo except trailer.

To find the towing compacity you will need to find your Curb Weight.

(Curb Weight) is the tow vehicle’s weight when filled with gas and other fluids it consumes while driving, but with no occupants or cargo.

I would take the truck to a recycling yard with a full tank of gas and drive it up on the scale the subtract any occupant's weight. This will give you your curb weight.

(GCVWR) Gross combined vehicle weight rating also known as (GCWR), is the maximum weight of a vehicle and its attached trailer. This figure also includes all occupants and cargo in both the tow vehicle and the trailer.

Now the ratings are set by the manufacturer and without that info there is no way to figure it out unfortunately.

I found this equation: GCVWR-Curb Weight=Towing Capacity

But without the GCVWR from the manufacturer I have no way of calculating it to find the towing capacity and the weight of the trailer will affect the end result.

I called GM customer service as well and they couldn't even tell me the GCVWR.

I did find some other useful information:
A gear ratio of 3.73 will lower the towing capacity as opposed to say 4.10's.

A C-Series 3/4 ton or a 1-ton class pickup could tow up to 12,000 lbs. (6 tons) of braked trailer.

Personally, I would keep it around 10,000 lbs. or less just to be safe.

When I spoke with GM customer service they suggested forums, that maybe your only option right now.

I tried looking at Haynes and Chilton for a manual, but they are sold out.

I also looked on eBay but all they have is a service manual. I did find some PDF Versions of owner's manuals but couldn't find what I was looking for maybe you will have better luck.

Here is the link:

http://forum.73-87chevytrucks.com/smforum/index.php?topic=30115.0

I hope this helps. Sorry, I wish I could do better for you but without that spec it isn't possible. I will continue to look and if I come up with it, I will send you a message.

Thank you,
Brendon
2CarPros

Hey Brendon, I think I found the answer. I found the trailering guide for 1984 on eBay, and for 1985 on a forum. The numbers matchup between years. If I’m doing my math right, my tow capacity should be about 12,500 lbs, which would include payload, and trailer towing. Does that sound right?

https://www.gmsquarebody.com/threads/1985-gm-towing-guide-and-1981-dealer-towing-video.16699/

https://www.ebay.com/itm/203707585193?mkcid=16&mkevt=1&mkrid=711-127632-2357-0&ssspo=tG-CKwfBRJq&sssrc=2349624&ssuid=pif6JwEGRI6&var=&widget_ver=artemis&media=COPY

Let me know your thoughts please.

Hey Brendon, I think I found the answer. I found the trailering guide for 1984 on eBay, and for 1985 on a forum. The numbers match up between years. If I’m doing my math right, my tow capacity should be about 12,500 lbs, which would include payload, and trailer towing. Does that sound right?

https://www.gmsquarebody.com/threads/1985-gm-towing-guide-and-1981-dealer-towing-video.16699/

https://www.ebay.com/itm/203707585193?mkcid=16&mkevt=1&mkrid=711-127632-2357-0&ssspo=tG-CKwfBRJq&sssrc=2349624&ssuid=pif6JwEGRI6&var=&widget_ver=artemis&media=COPY

Let me know your thoughts please.

Hello TWEBB101,

I'm sorry I just saw this. Let me take a look at it and I will message you back.

With the powertrain that truck has it shouldn't be a problem at 12,500 lbs. But let me look at those resources you sent me, and I will send you a message.

Thank you,
Brendon
2CarPros

Thanks Brendon. I think I miscalculated; I now have these numbers. Payload capacity max: 3,728 lbs (not including passengers), and Towing capacity max: 9,128 lbs (not including passengers or any payload). I've included the stickers I do have; they may help with calculating. Can you see if those new numbers match up to what you're getting?

Hello TWEBB101,

Thanks for the pics! Let me get into it and see what I come up with for you.

Thank you,
Brendon
2CarPros

Good morning, TWEBB101,

So, your (GVWR) or is the maximum a vehicle can weigh as it rolls down the road which includes curb weight and payload. Without knowing how much the truck weighs empty you can't find the payload. But payload isn't needed because we have the GVRW.

Payload is everything your truck is carrying. This includes everything in the bed and all occupants minus the curb weight.

So, 8,600 lbs GVRW = Curb weight+cargo+all occupants.

In order to find the towing capacity, you will need to subtract 8,600 lbs from the GCWR.

Unfortunately, we don't have that number because the sticker is gone, and the manufacturer doesn't have it anymore either.

Here is an article from Motor Trend I think you might find useful:

https://www.motortrend.com/how-to/gvwr-vs-gcwr/#:~:text=Gross%20combined%20vehicle%20weight%20rating%20%28GCWR%29%2C%20however%2C%20is,%28GCVWR%29.%20Is%20GVWR%20The%20Same%20As%20Payload%3F%20No.

There is no mathematical formula for the GCWR that I have available to me. It is set by the manufacturer and includes the vehicle, engine, transmission, axle ratio, optional equipment and trailer hitch type used.

I did find a towing and trailering guide on eBay. Here is the link:

https://www.ebay.com/itm/125836468320

I would buy it, or I would look for an owner's manual online.

I did find a towing capacity of 12,500 lbs. online as well.

I would say if you were alone towing something with a braked trailer and nothing in the bed you should be fine at 12,500 lbs in tow.

But if the vehicle is fully loaded meaning 3 occupants and the bed full of cargo, I would stay under 10,000 lbs in tow with a braked trailer.

Like I said earlier I would look for a manual, towing guide, or even an old brochure online because without having the GCVWR we cannot calculate the towing capacity.

Keep in mind even with that 454 it is still considered a light duty truck.

Follow this link for some additional information:

https://santafetowservice.com/blog/what-are-the-different-kinds-of-tow-trucks/#:~:text=A%20light-duty%20tow-truck%20is%20nimble%20and%20small.%20,Pickup%20truc%20...%20%201%20more%20rows%20

I wish I could help more but with the information we have this is the best we can do for now. I would check out these links and find and buy a trailer towing guide to get more accurate information.

Thank you,
Brendon

Thanks Brendon. I did purchase the towing guide, and I found the 1984 Chevy Truck vehicle information kit from GM Heritage as well. The towing guide says that the GCVWR is 14,000 lbs. The Heritage kit says the curb weight (minus passengers/cargo, just truck and fluids) is 4752 lbs. I'm happy to send those to you if needed/wanted.

Good morning, TWEBB101,

Awesome. Glad to hear you got the information you needed.

Yes, that would be awesome if you could send some info over. It will help someone else down the road.

Thank you,
Brendon