Another copy of one of my posts to the Yahoo group. Again, I'm not an official voice for Ford...just an ordinary consumer. If you choose to tow more than the recommended allowance (1,000lbs max)...you do so at your own risk.

However, I have no probs towing more....I've been told thru a few people that Ford has tested the FEH with 3x the recommended weight on their test track with no ill effects. Again, very unofficial FWIW.

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Busy day for me today. I have been considering purchasing a small
pop-up or travel trailer to go camping. The ones I really like are
closer to 1500-2000lbs rather than the 1000lbs advertised towing
capacity for the FEH. So, today I wanted to experiment a little bit
and see how the FEH behaves with a trailer. BTW, I installed a hidden
hitch (class III) with a 2inch ball--3500lb capacity.
I went to UHAUL and rented a 6x12 box trailer. This is the tandem
axle trailer with a claimer empty weight of 1800lbs. I drove around
for about two hours, a mix of interstate, two lane roads and city
driving. Terrain was light to moderate rolling hills with A/C on,
temps in the high 80s.
The FEH seems to do OK towing more than 1000lbs, provided you use
some common sense. I took it out on I-95 and cruised 60-65mph with no
problems whatsoever. I didn't want to push it, but I was able to set
the cruise and on rolling hills even with AC it had no problems
keeping speed. RPMs seemed about 500-700rpm higher than normal. Only
once did rpms top 4000--topped out about 4500 going up one moderate
hill. Acceleration was just fine, I didn't have any problems merging.
Two lane and city driving was just great...no probs. I think the
CVT is great....it was much easier to tow than my Escape v6(but it
has been a couple years so this is by memory). The CVT kept the rpms
where they needed to be...no gear hunting or lugging noted.
Acceleration with the CVT seemed only slightly slower than I remember
with the v6. FEH seemed really secure...never did I feel any control
problems. Oh....I didn't notice any sagging on the rear shocks
either. Braking seemed secure, but I wasn't in real hilly terrain.
You would definently want to watch your speed if you were in the mtns.
There was only one problem noted...backing up. Straight backing
was not a problem...even up a slight hill. However, when I was at the
UHAUL place they wanted me to back it up a hill into a tight space
(sharp turn backwards). With the tandem wheels, this sharp turn meant
the front wheels were "skidding" sideways rather than turning. The
FEH didn't respond in reverse...even when I pressed the pedal to the
floor. I guess it was too much torque for electric only. I turned on
the defrost to start the ICE, went fwd a few feet, and then put in
reverse to get a slight running start. I made it just fine the second
time...but had the pedal almost to the floor. Again, this was only
b/c of the tandem axles and it was a very sharp uphill turn. Had no
probs backing on a slight hill parking lot.
All in all, I was impressed and will have no reservations with
towing a 1500lbs trailer. Again, this is just MHO...I am no expert
here. Ford recommends 1000lbs...any more than that and you do at your
own risk. (Disclaimer).
Anyone else tow out there have any comments or
suggestions.

Nate

 

There was someone on one of the boards talking about towing a horse trailer with a FEH. I would assume that meant he had at least one horse in there at some time. Pretty gutsy.

I think the 1000# limit is quite conservative. My biggest fear of towing something heavier would be with the braking but that would be the case with any trailer. A trailer with surge brakes would eliminate most of that fear.

Backing up could also be an issue. There has been a good amount of discussion/debate regarding the limitations of reverse in these.

 

Any kind of engineering limit (towing limit, weight limit on bridges, etc.) is always a lot less than what has actually been tested. I would estimate it to be at least half of what the engineers would feel is safe. There are always going to be people that push and surpass the limits and you don't want to set a limit where people are going to risk disaster often.

 

Does towing a trailer "screw up" the regenerative braking?

The trailer has got to add a lot of drag, and I think would "rob" all the potential energy from the regenerative system. No?

 

Not exactly. In fact...most of the concerns people have shared with me on the Yahoo group regarding towing is the opposite....the lack of engine braking with the FEH compared to a normal ICE. (i.e. comparing an FEH to a regular Escape).

It is my understanding that the hybrid system will generate the power (regenerative braking) until the battery is full and then shut off. I don't think there is any way you can overcharge the battery. That is the same whether towing or not.

When towing you'll likely reach this battery "full" limit quicker and what happen afterwards is of concern. Not that you'l screw up the regenerative braking system...that now there is no engine (errr.....rengenerative braking) to help slow you down. The FEH doesn't have a true LOW gear...so once you run out of regen braking...you're pretty much using the friction brakes the rest of the time. Plus, since the electric drive is "helping", even at hwy speed...methinks it would need a recharge most of the time. I think with four wheel disc brakes and common sense (aka sensible speed) you'd be OK, but you would have to be careful when driving down a long mtn grade, for example.

If I was to do a lot of mtn driving, I'd seriously look into some type of electric trailer brakes...but on the East Coast I don't think it would be much of an issue. There were no issue whatsoever with my jaunt down I-95. Braking felt strong..never felt like I needed more. In fact, since I drive so gently...I'm betting that is probably when of the very few time I've actually used friction brakes on the FEH..other than to hold at a stoplight.

On the flipside, acceleration was fine with the trailer. You will use up your charge quicker (which may be what you were asking..now that I re-read your question). I can't imagine it being any worse than jack rabbit starts I see some people do...FEH or not. In my case, most of the time I made it to 10-15mph before the ICE clicked on in city driving. I really didn't detect any issues other than increased drag/weight. I don't think it is dangerous/damaging to the hybrid system...you'll just be using it more.

Nate

 

A couple of questions:

Doesn't the regenerative breaking stay on and the energy is dumped by reving the engine (the electric motor spins the ICE cylinders to bleed off excess energy to protect the batteries)?

I am not sure about the batteries being used to power the electric motor at highway speeds. When I look at the hybrid display, it shows that the ICE sends some power to the wheels (mechanical energy) and some to the generator whcih in turn powers the electric motor directly. The only time the battery is drained is if you accelerate and the assist kicks in for a few seconds.

Is there any kins of sensor in the FEH which can be used by Ford to estimate the load on the FEH? If I tow a heavy trailer and something breaks down the line, is there a way to trace it back to overloading the car?

Thanks,

Roch

 

Umm. That's not tremendously accurate. The FEH can and does use engine braking. Per your example, on a long mountain grade, eventually the engine will rev up crazy high.

I believe it fills the battery until it can't anymore, and then it revs the engine. I have had this happen a number of times with mine.

 

True. However you cannot keep the engine on constantly...like you can by shifting to a lower gear. The primary reason the engine revs is to take excess energy. With the CVT you're not directly connected to the drive wheels all the time like you are with a conventional tranny (the ratios are always changing). Also, the Atkins cycle engine provides less compression braking compared to a regular Otto cycle engine.

Nate

 

In the end, is the result not the same? If I go down a long hill coasting in L, the CVT will direct energy from the wheels to the generator (regenerative breaking) which in turn directs the electricity to the battery, then when the battery is full, direct the electrical energy from the generator to the elecric motor to spin the ICE (is that right, or is it a purely mechanical link from the wheels to the CVT to the ICE)? In either case, you should not need the actual brakes as long as the hill is not too steep.

Do I understand this correctly?

Thanks,

Roch

 

Nate,
Enjoyed your post; was curious if you could give me advice on installing a wiring harness in my 06 FEH FWD? (what parts would I need, etc.) Thanks! Jamie