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Discussion Starter #1
Anybody out there actually towing? Any advice? I might want a hitch, but not just for bicycles. I think I read one post where it was reported that range dropped significantly, which would be fine with me. But that is all I came across.

Anybody with anything to share about Bolt towing? A 200hp 266 torque 3500 pound vehicle.. I mean I know there will be naysayers, but given these specs the only issue I could see is maybe a structural one.

I personally have towed plenty of weight with less power and less torque before.
 

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https://oppositelock.kinja.com/tow-me-down-1609112611/1609771499 discusses why towing big trailers with small cars is common in Europe, but not in the US.

Basically, if you try to tow with a car and a trailer set up European style (with lower tongue weight), you need to stay within a low speed limit to be safe (many European countries have 80 km/h = 50 mph speed limits while towing). From the linked article:

Higher tongue weight, stable at 100 mph:


Lower tongue weight, becomes unstable at 65 mph:


Of course, higher tongue weight creates other issues for small FWD cars, so larger RWD or AWD vehicles tend to handle it better.
 

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The manual says the vehicle is not designed for towing. at all. Not that I'm telling you not to, just what the manual says.
 

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I'll be using mine for home store runs in town and the like, Torklift finally shipped my 2" hitch receiver yesterday, they are slow plus the holidays I assume... I have a little HF 4x8 utility trailer I used with my old car. I don't plan to do any highway towing with the car, just in-town pick up for sheet goods, appliances, that kind of thing. I briefly thought about a little teardrop camping trailer, but I think with the short wheelbase I'll just use one of those SUV/car tents for any mini camping outings for now. I do plan to build a nice little cargo box for the back eventually that will use the hitch attachment point for extra gear storage.
 

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Discussion Starter #5
Yes I have read about the Euro vs USA differences before. I do understand about the reasons.

Right BlackBolt, that is what I had in mind, a small light utility trailer for hauling 50 to 500 pounds of cargo. Plywood, mulch, a dirtbike maybe. I'd like to be able to hit the freeway..

I guess its a no go then, I'm not going to risk getting sued over this.
 

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transmission gear ratio and braking components

Surely there has to be some concern about the transmission and braking components when towing? Towing requires a gear ratio that is appropriate to towing up and down hills, rather than acceleration. Its my impression that the transmission gear ratio is a compromise between performance on hills, and acceleration, and if you add the weight of a trailer then the gear ratio must change to maintain the correct hill performance. Further, as the regen braking on the Bolt EV is likely set up to brake only the weight of the car, its highly likely it will not perform at all the same when towing. This will cause increased use of the friction brakes, and then questions about their capabilities.

I am sure towing a few hundred pounds will be fine, if intelligently done, but beyond that is likely a big deal. Its amazing how much the weights of trailers vary, for example. If you rent even a quite small u-haul trailer you are looking at upwards of 1000 lbs before you load up the trailer. This will create 100 lbs tongue weight, or more depending on the trailer.

Personally, I am waiting for an electric mini-van or SUV that can do about 3000 lbs towing, rather than risking wear and tear, and safety issues with my Chevy Bolt EV.
 

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Right BlackBolt, that is what I had in mind, a small light utility trailer for hauling 50 to 500 pounds of cargo. Plywood, mulch, a dirtbike maybe. I'd like to be able to hit the freeway..

I guess its a no go then, I'm not going to risk getting sued over this.
Don't be a wimp!

My Prius is rated to tow nothing, and I pulled a yard of dirt (I'm told 1800 lbs). I regularly tow a jetski weighing a couple hundred pounds; probably 400 with trailer. I've got a Torklift hitch, which I prefer due to the square receiver being the only part visible.

Use good judgement when towing and you'll be fine.

Harbor Freight folding trailer. Repacked bearing grease, but other than that stock.



 

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Same exact setup we had, right down to the gray Prius, but ours was an older '08 model with a 1.25" receiver. I wouldn't be too concerned with a couple thousand pounds behind most any small car in good repair, and the Bolt has a couple of pluses and a few minuses a as tow car.

Plus:

  • Weight
  • Power
  • Short rear overhang
  • Regen Braking
Minus:

  • Wheelbase
  • Weight distribution
  • Gearing
As long as you're pulling less kW continuously than the car alone running up the side of the Rockies at 85mph, your not putting any more stress on the vehicle drivetrain-wise than someone with a fat family who lives in the western mountain regions and drives briskly. I think it should take about 40kW extra to move a max GVWR Bolt up a 9% grade at 85mph vs level, as a quick example. Having a low gear would be nice if you were starting off on grade.

The springs likewise will see no greater impact than a lone car with four fatties in it, unless you load over the 2,258 lb rear GAWR with the tongue weight added in. The short wheelbase give the front end less leverage to keep the front tires planted, but conversely the short overhang gives the tongue weight less leverage to lift/unload the front end. Short wheelbases also tend to get a bit more bucky bronco over the highway seams, and they put more lateral load on the rear tires in cornering vs. longer cars. The more even weight distribution the Bolt has is a minor annoyance for towing, as a front heavy car would put more of the mass over the front axle, helping to counteract tongue weight effects.

Other than that, if you exceed the GVWR with the total weight of the rig, you need to slow down to maintain brake fade performance, or install trailer brakes. There is no special engineering that goes into making small general purpose passenger vehicles tow rated, just a series of calculations that are done to come up with ratings based on some arbitrary formula - based on what the formula writer thought the average driver would drive like in that sales market. In the US we now use SAE J2807, which is fairy new and has the average American driver idiocy factored in. Obviously if you are going 5 mph, you can tow several tens of thousands of pounds with a Bolt (or a bicycle with the right gearing for that matter) all day long every day without issue, as long as you have a way to bring it to a stop.
 

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Its my impression that the transmission gear ratio is a compromise between performance on hills, and acceleration
I would think, both hill performance and acceleration ask for a 'short' gear ratio. So, why would this require a compromise?

It is all about torque at the wheels, and looking at our 0 - 100 (or 60 if you like) times, I guess we have plenty of that :) My Outlander PHEV needs more than 11 seconds to reach 60 MPH, weighing about the same as the Bolt. So, torque at the wheels must be less. Yet, it is allowed to tow 1500 kg (in Europe, that is).
 

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The Mrs. and I installed the 2" Torklift hitch tonight. They still don't have the holes lined up right on the welding jig or whatever they use, or they might also be warping from the heat of welding to the cross bar. I enlarged 4 out of the 6 holes with a plasma cutter to get a nice slip fit to the bumper studs. She laid out the bumper fascia cut lines and I did the trimming with a jigsaw. The whole job was pretty easy, but I think we spent about an hour and a half by the time we cut the mounting holes to fit - I had to carry it back in and out of the shop half a dozen times, cutting a little at a time to get it all lined up just so.

It's a really nice unit, but they need to do more QA on these before they leave the factory. Shipping weight said it was 41 lbs. It's got a really tough textured powder coat on it too, I filed some off for starting my plasma cuts and it was very hard stuff to remove! I'm going to appreciate having that beefy 2" receiver opening when I make up my cargo box later on.
 

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Trailer wiring

I just got my car Dec. 22 and I want put the Drawtite hitch on. I am hoping that someone is going to come out with a plug and play wiring harness. I have contacted etrailer and they feel the Tekonsha kit 119250 should work. It is expensive but you just install clamps over the insulated taillight wires so no cutting into car’s wiring harness. Just a matter of finding the wiring harness before it goes into lift gate. I would love somebody to do this job before me and pass on any difficulties. I don’t need my trailer for a few months so I can wait and hope somebody tries this first.
Norm
 

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@redpoint, I have the same trailer! Towed it behind my '03 focus, now my '15 Jetta, and I'm sure one day when I care less about the warranty my '17 Bolt
 

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I just got my car Dec. 22 and I want put the Drawtite hitch on. I am hoping that someone is going to come out with a plug and play wiring harness. I have contacted etrailer and they feel the Tekonsha kit 119250 should work. It is expensive but you just install clamps over the insulated taillight wires so no cutting into car’s wiring harness. Just a matter of finding the wiring harness before it goes into lift gate. I would love somebody to do this job before me and pass on any difficulties. I don’t need my trailer for a few months so I can wait and hope somebody tries this first.
Norm
"Just a matter of finding the wiring harness before it goes into lift gate."

I'm in the same position as you: now have a trailer hitch but need to install wiring. The Tekonsha product does look like a good choice, but now need to find someplace to access the taillight and brake wiring, upstream from the tailgate itself. (The turn signals could be accessed from the bumper lights if no other locations is easier.)
If you find a good location, PLEASE POST, PREFERABLY WITH PICTURES. I think there are a number of us trying to figure this out and patiently waiting for the first one to get it done and post it.
 

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Trailer Wiring Finally Installed

After waiting for a detailed post on just how to wire the Bolt for a trailer, I decided to proceed. What follows is how my Bolt was successfully wired. I had this done by a mechanic I trust and the process took over 2 hours. It would probably be much quicker when one knows where to find the wires. Since I didn’t do the actual work, I can only give a description of what I saw.
1. I purchased a Tekonsha ZCI harness #119250 to avoid splicing into the wiring of the Bolt. The harness wires clamp around each corresponding car wire and pick up the signal of an electric current flow. That means four clamps (right and left turn, brake, taillight) The harness could be removed with no damage to the original Bolt wiring.
2. As many probably already know, the brake and tail light functions in the bumper work only when the tailgate is open. This means we had to access brake and taillight wires somewhere upstream from the tailgate lights, not the bumper lights. Maybe someone can figure how to defeat the GM system that activates the bumper brake and tail lights only with the tailgate open. This would make trailer wiring easier.
3. The right and left turn signals can be activated from the bumper wiring and those are accessible on each side behind the bumper itself.
4. The brake and taillight wiring was accessed by removing the upper rear panel (right or left, don’t need both) in the cargo area. We used the left rear panel. (see photos) Remember the Tekonsha clamps are directional so it matters how they are applied over the wires. The current runs upward toward the roof. Otherwise the attachment process is straight forward.
5. The Tekonsha control unit was attached behind the lower left panel and the trailer wire fed behind the rear panel (which was removed) and then down and out behind the bumper where the trailer hitch had been installed. There was a notch already there from the hitch.
6. The harness needs its own separate and fused 12V line which was fed from the battery (under the hood) and then below the car, coming up in front of the bumper into the same area that the trailer plug exits. Twist ties hold it to the frame but the wire is outside the car. I’m not sure what it would have taken to somehow tunnel it inside the car and still not be visible.
7. The Tekonsha module has a “learn” function, so if it doesn’t work at first it may need to be “taught”.
Feeding some of the wiring without a lift to get under the Bolt could be a real pain.
So far the unit works perfectly. I hope it was built to last since accessing the wiring is not the simplest. Hope this helps others who are planning on installing trailer wiring.
 

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Somehow the photos were rotated 90*. Up is to the left.
I've found that forums auto rotate uploaded photos so that the longest edge is in the horizontal plane.

In other words, if you take a photo with your phone upright instead of sideways, it will be taller than wider. When you go to upload to the forum, the photo will be rotated so it is wider than taller.

Tip #1- Always take photos in landscape mode (sideways) rather than portrait (upright) on your phone
Tip #2- To force a photo to have the correct orientation on the forum, make sure the horizontal side has at least 1 more pixel length than the height. You can chop the height down below the width, or you can add empty white space to the sides until it's longer than the height.
 

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The manual in my Mazda3 says the very same thing:
CVT, Auto, or manual transmission?

Most auto transmissions have a lockup torque converter now. It doesn't prevent the tranny from extra stress during initial acceleration, but after lockup it shouldn't cause overheating issues. I'd be nervous towing with a CVT considering the inherent fragility. Manual I'd tow all day.
 

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I cooked the transmission in an AMC Eagle (Chrysler transmission) towing a camp trailer with frontal area nearly as large as that. Nothing broken. $1k to replace all the fried seals, inside and out.
CVT, Auto, or manual transmission?
Manual transmission of course, would not have attempted that in a car with a slushbox.

Granted I only towed that trailer once, but it was about 75 miles across L.A. Freeways which included some stretches at 55MPH (wasn't going to speed towing that thing), some stop and go traffic and going up and down a good sized mountain pass with a 5.5% grade. I have a small utility trailer I used to tow regularly when I was autocrossing sometimes more than 200 miles per day towing about 600-700 pounds.
 
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