OT - Trailer Tow Vehicle - Capacity

I am going to try pulling a trailer with my 2.5l, 110hp, 135lb/ft torque Oldsmobile. The owners manual says it can’t tow anything, but I will just be pulling canoes and keeping the speed reasonable. Also, I am getting a mechanic to give it a good tune-up and go over all the key parts.

I was looking at other cars, and I can’t understand how vehicles get their ratings. For instance, the Buick LeSabre is only rated for 1000lbs, despite being considerably more powerful and heavier than the Toyota Corrolla (1500lb rating), or the Hyundai Elantra (3500lbs with trailer brakes). The Yaris even has a 750 lb rating and it is much smaller than my car.

Can anyone explain why so many passenger cars can only tow 1000 lbs? Does anyone have any recommendations on a small, fuel efficient car that can also comfortably pull a small trailer?


Just a thought,
as I’m not an engineer, but pulling the load forward is what the power does.

But the vehicle also has to have the frame/body structure to support the load, and the suspension as well.

Then there’s the brakes. Stopping with an additional load in a safe manner is quite important.

Best of luck, keep the trailer very light if you choose to do it.


HP and torque
alone aren’t the only factors that determine how much a vehicle can tow. Other factors include axle gearing, transmission gearing, transmission cooling, suspension, frame, and brakes. You also have to keep in mind that when towing a trailer of any kind with any vehicle you have to subtract the weight of any cargo you are carrying in the vehicle from the vehicle’s towing capacity.

Thanks . . .
I understand the idea of considering the whole vehicle, not just the engine, and the gross weight. I guess I am just surprised that a little corolla can tow more than a full-sized Buick with a V6. Moreover, if the full-sized Buick has four 200lb occupants, its remaining capacity could be as little as 200 lbs?!?!

Are they (car companies) just being very conservative in their estimates? Are cars built so differently now than a few years back? Is it because they assume anyone wanting to tow will just buy a pickup or SUV?

Thanks for your suggestions/info.

Answered your own question
"Is it because they assume anyone wanting to tow will just buy a pickup or SUV?"

Change it to “Steer you to an SUV”, and you’ve got it. American manufacturers until just recently didn’t make much, if any, money on cars, but were making huge margins on trucks & SUV’s.

Foreign manufacturers don’t have that reality outside North America, so they make their cars able to do most everything, and advertise them as such.

Ask U-haul or maybe Draw-tite

– Last Updated: Mar-11-08 11:22 AM EST –

I think you will find that if they make a hitch for the Olds, you will be okay.....

(Yeah I corrected it..but the point is the same...If there's a hitch to fit, towing a light aluminum trailer with a canoe or kayak will NOT be a problem...)

Hitch Class
There are five classes of hitches. Class 1, is what can be found on most light cars, 1 1/4" receiver, and the hitch is limited to 1000lbs.

The limiting factor has to be how the hitch mounts to the vehicle. If your manual doesn’t acknowledge teh ability to tow, then there is probably not a hitch that will bolt on. However, cozy up to a welder and anything can be done.

Todays cars are …
mostly unibody, either foriegn or domestic. Towing capacity is somewhat based on body construction, example: I had a 04 Toyota Tacoma DBL cab. It had a 190hp V-6 automatic,and full frame & 4WD. It could tow 5000lbs. I now drive a RAV4 269hp V-6 automatic 4WD with tow package. It can tow only 3000bs. The drive line is almost the same, the horse power is higher then the truck,but the RAV body is a unibody,and hence the lighter rating. Agree with others ,follow the tow specs in the manual. Most of the specs,are below the capacity of the vehicle,but you can thank lawyers for that one. You should be able to find a hitch for your car. There are plenty of manufacturers out there. Home made welded hitches may void any warranties on the car. Factory hitches use engineered strength points of the frame,or body. Home made hitches may not. Good Luck.


Class I limits

– Last Updated: Mar-11-08 3:27 PM EST –

Class I hitches may have up to a 2000 lb limit, depending on the tow vehicle used (even if it's the same hitch!). See http://www.blackhillsrv.net/bhrvr/hitchclasses.html for more info.

The limiting factor is whatever the WEAKEST part of the entire system is. That could on the tow vehicle OR the hitch hardware OR the trailer itself.

For example, my truck has a Class III hitch that happens to be rated to 6500 lbs. (To be considered Class III, the hitch must be able to tow 5000 lbs. 6500 lbs is more than the Class III rating but it is less than Class IV's rating.) However, the truck itself is rated to tow 6300 lbs, and the hitch BALL (replaceable) is rated to 5000 lbs. The trailer itself can carry up to 1300 lbs.

Don't exceed any individual spec.

Trans cooler
If you decide to tow with it, I would strongly suggest adding a trans cooler, semi-metallic brakes, and heavier (if available) struts.

Your vehicle, if properly set up, should tow up to about 10% of it’s weight safely. I towed a 2000lb starcraft with a Mercury Topaz 2.3l 4 banger for 5 years with little problem, But the maintainance costs went through the roof (extra oilchanges, brakes, struts, tires, etc).

Best bet is to go to a reputable independant garage and ask their opinion

Good Advice
Thanks for the tips. I went to a mechanic and was told the tranny cooler would be unecessary in this car because of the relatively small engine mated to a solid transmission. He figured it just wouldn’t get that hot. He and I did agree, though, that plugs/wires/sensors/shocks/brakes/belts/filters would all be changed out before I go.

My car was available as either a 4 or 6 cylinder, and only the 4 cylinder isn’t supposed to tow. As such, I think the frame, brakes, and suspension will be up to the task, the engine might just need a bit of coaxing.

Thanks again.

Be careful about mechamic’s advice

– Last Updated: Mar-12-08 1:13 AM EST –

He may be trying to save you some cash, but the road to hell is paved with good intentions. If the transmission cooler manufacturers list a cooler to fit your car or the auto manufacturer recommends one for towing, get one installed.
It is cheap insurance, compared to what you will pay to rebuild your transmission or if you over heat it and fry your PCM. As a victim of a fried PCM and wiring harness thanks to tranny over heating on my '02 Mercury Villager (a 3.3l V6), that is tow rated at 2500 lbs(a $1400 lesson)I wish I had spent the $185 for the cooler.

PS, I used to have an '85 Cutlass Wagon with a 2.5l 4 with an auto trans. It came equipped with a trans cooler standard and was rated at 1500 lbs towing capacity. I replaced it with the exact same vehicle in '90 and the owner's manual said thet towing was "not recommended". The only real difference between the two was that the '90 no longer had the cooler as standard equipment.

keep me posted
on your experiences. The new unibody frames and front wheel drive are somewhat different from the old M-543-a2 I use to drive.

about add on trans coolers
If you do decide to install an add on trans cooler, keep in mind that the “cooler” usually also serves as a heater, keeping your tranny fluid at the same temp as the water in your cooling system. If the OEM trans cooler is located in the outlet tank of the radiator, the fluid is heated to at least 130 degrees. Why does this matter, some of you Southerners are thinking? Cause it gets mighty cold in some parts of Manitoba.

When installing the cooler, put it upsteam of the radiator mounted cooler- this will radiate excess heat and still keep the fluid closer to designed operating temps.

Tell us how it works out,


Lost me . . .
OK, I will go for the cooler. I want to keep this car for a while, and the argument that it used to have a tow rating is convincing.

I’m not sure I understand the bit about where to place the cooler relative to the radiator. I will not be doing it myself anyway, but would like to be able to ask my mechanic without sounding as ignorant as I really am!

Also, Manitoba does indeed get very cold sometimes. You got that right, so you must be trustworthy!

Thanks again for all the tips.

Does your auto trans have overdrive??? If it does DO NOT TOW IN OVERDRIVE EVER!!! That is one sure way to kill a tranny while towing, especially a less robust older tranny.

What “upstream” means

– Last Updated: Mar-12-08 1:01 PM EST –

The fluid from your transmission already flows through pipes to and from the "cooler" in one tank of your engine's radiator. The auxiliarry cooler disapates heat directly to the air, so it can over-cool the transmission oil in winter weather. Hook up the auxiliary cooler so the fluid flows through it first (that's the "upstream" part of the above explanation). That way, if the fluid gets over-cooled, it can then get warmed up as it passes through the "cooler" (but in this case it acts as a heater) in the radiator before going back to the transmission.

There's another "upstream" to this story too. It's best to put the auxiliary cooler in front of the engine radiator, so it's exposed to cooler air than it would be if mounted behind. There's plenty of reserve heat-exchange capacity in the engine radiator to tolerate a bit of extra warm air coming in the front, but the same may not be true of the transmission cooler.

The transmission should be “smart”…
…enough to know when overdrive creates too much load and shift down to drive, just like it does when you go up a hill. If it shifts back and forth a lot, that’s extra wear and tear which serves no purpose, and manually downshifting to prevent that is good.

You might
be correct where the absolute newest computerized auto tranny’s are concerned. But in my experience, every vehicle I’ve owned, my father has owned, and my uncle has owned, the owner’s manuals specifically state to NOT tow with overdrive engaged that it will cause damage. My uncle tested that theory once, he forgot to disengage OD, and burnt up his transmission in about 200 miles and had to be towed off the highway. My Explorer is a 2003 which is fairly new, and owner’s manual tells me to disengage overdrive.

Overdrive gears are higher gear ratios to sustain higher speeds at less RPMs with less resistance - they aren’t geared properly to handle the load of towing. Besides a constant shifting issue, it is also a heat and wear/tear issue on the gearing.

I think the instructions for my car,…

– Last Updated: Mar-12-08 1:45 PM EST –

...which is a '95 Blazer, say the same thing. Another thing I was going to add to my above post, which I'll say here instead, is that the first thing the transmission does if the load is a bit too great for overdrive, is unlock the torque converter, which has the same effect as downshifting, but the slippage creates heat along with the extra torque. Usually in that case, if you downshift manually, the RPMs will be just about the same as if you stayed in overdrive because while in the lower gear the torque converter will stay locked, so there's no slippage. That's a better situation to be in, because heat production is much less.