Prius Towing Capability

Moshe, I'm not sure of the rules in your part of the world but in Australia it is unlawful to tow in excess of the manufacturers permitted towing capacity. In Australia the towing capacity is 0. A bit of a pitty because I'd love to be able to tow my motorbike on a small light trailer but even though it would weigh only 300kg (660lbs) all up, I cant.

 

<div class='quotetop'>QUOTE(moshe_levy @ Sep 17 2007, 07:50 AM) [snapback]513607[/snapback]</div>

Moishe,

All of the earlier Prii (2001-2007) came with the statement that towing was not a good idea. The earlier (Classic) Prii have had a small number of transmission failures (perhaps prevented by periodic ATF - tranny fluid - replacement) so I agree with the restriction. The hitches that you have seen are typically intended for use with bicycle carriers, not towing (although limited, low-speed, and lightweight use may be OK).

If you add a hitch, remove it when visiting your dealer to avoid later warranty discussions.

JeffD

 

The 2004-2005 owners manual says "Towing not recommended". Maybe they fear the braking system might not handle the weight of the towed load. I don't expect small trailers come (or can be fitted with) brakes to alleviate this potential issue. The 2006 (and I presume later) manual ALSO says something like "hitch mounted bike racks and cargo trays not recommended". I guess that happened after the forum voyeurs from Toyota (which presumably also brought us some 'requested' changes) noticed people posting their pictures of hitch mounted racks and cargo trays. Not sure WHY this would be a problem unless they fear hanging too much weight off the back would lift the front a bit. If that IS the case, a small trailer would actually put less weight on the rear end.

Note that the service manual ALSO has a reference that some maintenance items (like oil changes) should be done more frequently when towing.

 

my manual also says not reccomended and it wouldnt list the capacity and if their was any, it would defeinietly be listed on the vehicles placard. i checked there and nothing.. there are multiple considerations when towing, the capacity of the tow and the tounge load which is the weight that is pressing down on the hitch.

if you need to actually tow something perhaps you should consider purchasing something else

 

<div class='quotetop'>QUOTE(moshe_levy @ Sep 17 2007, 07:50 AM) [snapback]513607[/snapback]</div>

I purchased my hitch from U-haul (hitched made by curt)...it is specifically designed for the Prius and has a maximum tongue weight of 200 lbs, and maximum weight capicity of 2000 lbs. You can save yourself the shipping and price by just walking into your local Uhaul dealer and purchasing it there for about $120.

Those are the listed maximums, but I am not sure the prius could handle that much...I have towed a motorcycle trailer (about 2500 miles, with a 15% loss in MPG) and a utility trailer (with a riding lawnmower, did not exceed 750 lbs) and it handles really well...just a little of the small car feeling.

It is at your own risk, but if you are looking to haul large loads, it should be just fine.

 

<div class='quotetop'>QUOTE(faith2walk @ Sep 18 2007, 10:15 PM) [snapback]514639[/snapback]</div>

Can you post a picture of the rear with the hitch? I wonder how low it hangs and clearances with muffler, etc.

 

<div class='quotetop'>QUOTE(bruceha_2000 @ Sep 18 2007, 03:15 PM) [snapback]514431[/snapback]</div>

Speaking of towing and braking, here is a philosophical question for the techies -

Given that the regen braking system of HSD converts the forward energy back into electricity, would the added weight of the trailer produce more regeneration by the braking system since there is more weight to bring to a stop? :huh:

I'm sure it has to amount to a net loss anyway since it would also take more energy to accelerate with the heavier load, but something interesting to ponder...

 

I had to tow with my Prius before.


I busted the front spindle of my go kart and had to pull it back up the hill.

 

<div class='quotetop'>QUOTE(faith2walk @ Sep 18 2007, 11:15 PM) [snapback]514639[/snapback]</div>

I purchased the same Curt Trailor Hitch made specifically for the Prius on line. I had asked my dealer before I bought my car, since they did not have a trailer hitch, if I put one on would it void my warrenty. They said absolutely not. I have a 5 X 8 Utility Trailer. I hauled 10 80 lb bags of concrete with absolutely no problems and it was up hills. It handled very well. True you will loose some in fuel economy. I also hauled my 20 HP Scott Garden tractor on a different occasion with out any problems.

If I were you, just check with your individual dealer that you would be having your service done. and just ask them if it would void your warrenty.

I installed the Curt hitch in just one hour. There are two towing brackets under the rear of the Prius. You unbolt them. There is a faccia underneath on the left side that has to be trimmed a little to go around the trailer hitch. I used a pair of sissors. Very easy. New bolts are provided. The hitch just bolts up to where the towing brackets were. Be sure to torque the bolts to the recommended tightness. I believe it was 35 lbs. NO WELDING OR ANY OTHER MODIFICATION IS NECESSARY. AND IT DOES NOT INTERFERE WITH THE MUFFLER.

Richard

 

Here's another angle to consider. The Prius manual says it's designed to hold 600lbs of people/cargo. Most likely, the folks that load bikes on a carrier, or a light trailer, rationalize that if (for example) they weigh 200lbs, then certainly towing a 400lb trailer/load is tantamount to the same thing as maxing the 600lb people/cargo capacity. Of course if the Prius had to go in for warranty related repairs, you better not have a hitch welded on

 

<div class='quotetop'>QUOTE(alg @ Sep 19 2007, 10:14 AM) [snapback]514828[/snapback]</div>

More than you ever wanted to know or see.
http://evnut.com/prius_hitch.htm

 

Ive towed two motorcycles w/ trailer totaling 1250 lbs, from LA to Vegas no problem.

I'm getting ready to try three bikes with three people totaling 1750 lbs towed and 650 in people and cargo.

That is 60% of the curb weight where it seems like most sites say that anything under 65% is pretty safe. (in regards to weight and handling issues) above 65% they recommend stabilizers.

The only real question I have about the Prius is "How is the load transferred through the CVT/Planetary gear?"

This is the only weak point I see. Given the redundant regen braking and friction brakes I am not worried about breaking ability. (given careful driving habits of course)

If the Planetary gear is able to spin up and transfer more torque by higher RPMs I think it should be OK, but if it just forces the .... ofrce through the gear, then it could dramatically increase the load on the gear.

 

<div class='quotetop'>QUOTE(darelldd @ Sep 19 2007, 02:14 PM) [snapback]514911[/snapback]</div>

I'm NOT WORTHY!!! Excellent pictures. Worth having a hitch just to keep tail gaters from scratching your rear bumper.

 

<div class='quotetop'>QUOTE(Devil's Advocate @ Sep 19 2007, 02:19 PM) [snapback]514914[/snapback]</div>

I think you are REALLY pushing it there. Even the 1250 lbs. The Prius is FWD and a lightweight.

The planetary gear probably isn't a too big a problem. I've seen one in real life and I thought it was about the same size of a planetary gear from an automatic transmission. My worry would be the transaxle getting too hot and breaking down the fluid. The Prius doesn't have a direct "transmission" oil cooler.

 

<div class='quotetop'>QUOTE(Devil's Advocate @ Sep 19 2007, 02:19 PM) [snapback]514914[/snapback]</div>

I think you are REALLY pushing it there. Even the 1250 lbs. The Prius is FWD and a lightweight.

The planetary gear probably isn't a too big a problem. I've seen one in real life and I thought it was about the same size of a planetary gear from an automatic transmission. My worry would be the transaxle getting too hot and breaking down the fluid. The Prius doesn't have a direct "transmission" oil cooler.

 

Devil's, as you know there are significant uphills this route. Without some means of tracking temperatures on the 'electricals' side, I would not attempt this task.

Suggest you take a look at scangauge or canview and see if they'd help. Upgrades to these products are underway and I haven't kept up on the Prius-specific capabilities

In any case, this level of NHW20 'workout' also makes you a great candidate for draining the trans. fluid and having it analyzed. Up for that? We were going to suggest you change that fluid at some point anyway.

 

I bought the same trailer hitch from www.etrailer.com. The hitch cost was $125, and if you spend more than $150 then shipping is free. I purchased a little black rubber cover to plug the square hole when not in use, and a matching lock for the hitch tongue and cable to lock the bikes in place. Total cost was about $160, but no shipping cost and no taxes, and it was delivered to my door.

Those pictures of the damage scared me at first, but I remembered checking the path of the exhaust and did not see a problem. I must have the redesigned hitch. I will check it this afternoon.

The hitch looks great, and does not drop any lower than the plastic air dam on the sides.