Economical tow vehicles

[redpoint5]

Originally Posted by Taylor95

we will be getting a Rav4 Prime (if we can find one) in the near future. That has a tow rating of 2500 lbs. If We can find a trailer light enough, the Rav4 would definitely be very economical, especially because I might be able to tow with the electric only driving capability.

Does anyone know how tow ratings are determined? Are there any negatives to towing above the capacity by a few hundred pounds? I assume that the Rav4 Prime would be limited in the areas of suspension and perhaps the frame. I would think that there is plenty of pulling and braking power to tow well above 2500 lbs.

Edit: Supposedly the only relevant difference between the Rav4 Prime and the Rav4 TRD Adventure (tow capacity of 3500 lbs) is that the latter has a transmission cooler. Would simply adding a transmission cooler be sufficient to tow a little more?

Very interested to hear your comments about the RAV4 Prime once you have time with it.

I believe the Prime has an eCVT, so there's no need for a transmission cooler since it doesn't have a torque converter (where slipping occurs and waste heat accumulates).

There's no issue towing above rating given the operator knows how to handle the load and conditions. I've pulled close to 2,000 lbs in my Prius which has no tow rating. I took it slow and made sure to leave a very large gap between me and the traffic ahead. I didn't go far.

[hayden55]

Originally Posted by redpoint5

Very interested to hear your comments about the RAV4 Prime once you have time with it.

I believe the Prime has an eCVT, so there's no need for a transmission cooler since it doesn't have a torque converter (where slipping occurs and waste heat accumulates).

There's no issue towing above rating given the operator knows how to handle the load and conditions. I've pulled close to 2,000 lbs in my Prius which has no tow rating. I took it slow and made sure to leave a very large gap between me and the traffic ahead. I didn't go far.

Yup. Never had any issues with heat over 100k miles of somewhat downright abuse on my ecvt prius. Only had one time where i was like 90% throttle for about 25 minutes straight on i-49 going 75mph north (a road where truckers struggle to maintain 40 up hill) and i killed the battery. lol
Car just stopped accelerating and then it charged up in about 60 seconds and was good to go again. In my head I was like oh F i killed it. Nope.

*forgot to add i was towing two jet skis

[Taylor95]

Originally Posted by redpoint5

Very interested to hear your comments about the RAV4 Prime once you have time with it.

I believe the Prime has an eCVT, so there's no need for a transmission cooler since it doesn't have a torque converter (where slipping occurs and waste heat accumulates).

There's no issue towing above rating given the operator knows how to handle the load and conditions. I've pulled close to 2,000 lbs in my Prius which has no tow rating. I took it slow and made sure to leave a very large gap between me and the traffic ahead. I didn't go far.

That would certainly be a bonus if I didn't need to put in a transmission cooler. After reading about what kind of things Ecomodders tow, I am confident that a measly 400-500 lbs over the tow rating won't be problematic. Since there is no "tow package", I will have to put in a hitch and a 7 pin connector.

I just watched a video where someone towed 2000 lbs in their Rav4 hybrid (500 lbs over) and it performed very well. I expect the Prime to be perfect for our needs.

I expect to get both the car and trailer in late July/early August, so look for an update around then.

[cRiPpLe_rOoStEr]

Originally Posted by redpoint5

I believe the Prime has an eCVT, so there's no need for a transmission cooler since it doesn't have a torque converter (where slipping occurs and waste heat accumulates).

Not so sure if the torque converter is really the one to blame, considering many conventional automatics are suitable for towing, and some extraheavy trucks feature one instead of clutches which also tend to overheat under some conditions. But anyway, considering the power-split device relies on a planetary gearset, just like the wheel hubs of some large trucks, this seems quite a safe setup for towing, not to mention Toyota claims one of the main advantages of the HSD system to be its scalability allowing it to fit from subcompacts to larger SUVs and even some commercial trucks.

[redpoint5]

Torque converters can be made robust for towing, especially with extra cooling.

The problem is all that slippage causes heat, and the transmission fluid loses its properties once it heats above a certain temperature.

I wonder if Toyota's eCVT could scale up to semi truck size and actually be more efficient with a hybrid setup? No gearbox, and always in the right "gear".

[cRiPpLe_rOoStEr]

Originally Posted by redpoint5

I wonder if Toyota's eCVT could scale up to semi truck size and actually be more efficient with a hybrid setup? No gearbox, and always in the right "gear".

It may be possible, even though those Hino hybrid trucks feature a power-split device along a gearbox.

[RoBoBob]

[QUOTE=Taylor95;651399]
There is one more thing I would like to mention: we will be getting a Rav4 Prime (if we can find one) in the near future. That has a tow rating of 2500 lbs. If We can find a trailer light enough, the Rav4 would definitely be very economical, especially because I might be able to tow with the electric only driving capability."

I had a Mazda CX5 rated to tow 2000 lbs. (USA), but found it was poorly suited to tow a boat nearing its tow rating due to the short wheelbase. If the trailer you tow is not very long, the RAV4 would do fine. You will definitely know that you are towing from the performance (the little trucks work hard to make the trailer move). But if it's a long trailer, you run the risk of the "tail wagging the dog" as the trailer loading can cause the duo to sway at the coupling (trailer hitch) - possibly some of the sway control packages for towing can fix it, but you don't want it to catch you/your wife by surprise. It could case a crash.

[Ecky]

[QUOTE=RoBoBob;651840]

Originally Posted by Taylor95

There is one more thing I would like to mention: we will be getting a Rav4 Prime (if we can find one) in the near future. That has a tow rating of 2500 lbs. If We can find a trailer light enough, the Rav4 would definitely be very economical, especially because I might be able to tow with the electric only driving capability."

I had a Mazda CX5 rated to tow 2000 lbs. (USA), but found it was poorly suited to tow a boat nearing its tow rating due to the short wheelbase. If the trailer you tow is not very long, the RAV4 would do fine. You will definitely know that you are towing from the performance (the little trucks work hard to make the trailer move). But if it's a long trailer, you run the risk of the "tail wagging the dog" as the trailer loading can cause the duo to sway at the coupling (trailer hitch) - possibly some of the sway control packages for towing can fix it, but you don't want it to catch you/your wife by surprise. It could case a crash.

I've found this is particularly an issue if the center of mass is behind the trailer's wheels. The farther forward from its wheels the center of mass is, the less likely it is to wag the back of the tow vehicle.

[RoBoBob]

[QUOTE=Ecky;651844]

Originally Posted by RoBoBob

I've found this is particularly an issue if the center of mass is behind the trailer's wheels. The farther forward from its wheels the center of mass is, the less likely it is to wag the back of the tow vehicle.

That outboard motor on the boat is reluctant to shift forward. But, yes, you are spot on about how a trailer is loaded will make a big difference. It also reminded me how overloading the tongue can make the front wheels "light" (and in RAV4s that's the drive wheels, even with AWD). Which can be another major issue when braking (weight shift exacerbates) or accelerating.

[Taylor95]

I definitely should look at some things to help with towing, such as airbags. I do not anticipate much of a problem though. The trailer that we will get will not be excessively long. The Prime is also very heavy at 4300 lbs, so I think that maintaining control of a <3000 lb trailer should not be too much of an issue. But I agree that this is something important to pay attention to though.