Towing and le overdrive

[StrangeWill]

So with autos this seems to be a big no-no most of the time. Wondering if this applies to a manual too.

Of course foot to the floor in 5th isn't reasonable, but I'm driving for 28 bloody hours, and a lot of it is going to be flat. Do I really need to be puttering along in 4th the entire way?

Opinions? Comments? Smartass remarks?

[IMBoring25]

Unless you're towing in excess of what your vehicle is rated for or there's a specific warning in the owner's manual, I'd treat it just like the one-more-gear it is. The only reasons I ever lock out overdrive towing in an automatic are to keep it from hunting, to pre-select power to pass or climb a hill, or to control speed on a downhill section of road.

[theholycow]

Totally depends on vehicle, speed, and trailer.

Manuals don't suffer from the heat issue like automatics do, so I imagine it's ok.

Overdrive while towing isn't a problem for my automatic.


That's my automatic, a 5800 pound 24' travel trailer, and a boat trailer on top of my ladder racks.

[Rope-Pusher]

I assume taht if you were doing something wrong with towing with a manual, you'd probably know somehow. Not always the case with an overheating automatic (although HD trucks generally at least have a temperature gauge for the transmission, but I don't think I've ever seen one in a non-HD truck).

You will probably be fine. Sometimes they will print warnings about never towing ANYTHING with a unibody car. There is one in my manual. But I assume they just don't want people towing a semi or something. A CYA (cover your ass) thing. You'd probably be fine towing a reasonably sized trailer.

but thats me, I have zero towing experience. I have banged many a leg on damn trailer hitches, though.

On the average, I probably tow something once a week. Might be a light 4'x8' utility trailer or it might be some trailer that starts to near the tow capacity of the Jeep. When the trailer is tall and catching a lot of wind or heavy and catching a lot of hills, I try to be pre-emptive on downshifting and run a gear lower. I also tend to drive 5-10 mph slower as the trailer approaches the trailer tow rating. (takes the worry about being close) When the trailer is light, the road is flat and /or the wind is at my back, I leave it in 6th mostly and drive at the speed limit or so.

Most all vehicles have some sort of a tow rating - not all, I said most all. Some of the criteria that go into trailer tow ratings are vehicle structure & suspension, vehicle brake capacity, clutch heat capacity, vehicle heat management, trailer frontal area, and weight of passengers and cargo in the towing vehicle. Engine power isn't always a limiting factor. It's interesting to see what the trailer towing option package might include. Often the alternator and battery, radiator, and slushbox fluid cooler are upgraded. Jeep adds synthetic fluid to rear differential often-times. Might also include trailer hitch, trailer wiring harness, brake upgrade, suspension upgrade, full-sized spare tire, revised differential gear ratio, electronic brake controller (or just wiring for it) and trailer wiring adapter. Unibody vehicles can tow (7000+ lbs for Jeep Grand Cherokee w/Hemi), but they do need to be designed with towing in mind if you want to see a generous trailer tow rating. Oh, and trailer tow ratings in Europe are crazy. Same vehicle as sold here might have 50-75% more towing capacity. They are big on not smoking the clutch after repeated uphill launches, but they assume the tail may wag the dog if the trailer towing drivers don't anticipate conditions and slow down when required and that's the driver's responsibility to take care of. Also, they don't have the combination of mountains and desert like the American Southwest, so their cooling systems are not taxed as hard.

[Tups]

I've had no problems with towing on the highest gear for long periods of time. Of course the trailers I've towed haven't been from the heavier end, but I have never heard of anyone having problems with the gearbox.

[Rope-Pusher]

I've had no problems with towing on the highest gear for long periods of time. Of course the trailers I've towed haven't been from the heavier end, but I have never heard of anyone having problems with the gearbox.

I don't know that it's a matter of having gearbox problems as much as it is of having the wrong gear ratio with the extra mass, wind resistance, etc. If the top gear ratio was optimized for the towing situation, it would feel like one-gear-down any time you weren't towing, which is most of the time for most vehicles, so they optimize for the non-towing condition and then you downshift to get back your gradeability, etc. when you are towing. A lot of folks here think fuel mileage is directly proportional to the engine rpm, but that isn't so. Slowing the engine down by 30% at a cruise does NOT save you 30% on fuel - it's probably closer to a single-digit percentile, especially when you consider that with a trailer behind you, it takes more power to drive down the road and the engine efficiency at higher loads is generally better at higher rpm. Tubey shur, you would need to look at the BSFC vs rpm and power output curves and have an understanding of the road-load horsepower your situation requires.

[theholycow]

Engine power isn't always a limiting factor.

It shouldn't ever be a limiting factor...tow ratings are supposed to be about safety, and if you're towing so much that your vehicle can't pull it fast then you probably need to go slow anyway.

However, I guess manufacturers also have to worry about warrantying vehicles...so a vehicle that can safely tow a given amount but will be slow may have a lower rating...

[Tinton]

I think it depends on the powerband of the engine. If it can't handle towing a trailer at 2000RPM in 5th (or 6th) and you have to floor it just to keep moving, perhaps you should select a lower gear where you don't need to use so much throttle.

[comingbackdown]

(although HD trucks generally at least have a temperature gauge for the transmission, but I don't think I've ever seen one in a non-HD truck).

Dad's Dakota has a transmission temp warning light.

[theholycow]

I suspect that most modern automatics have a warning light for trans temp.

I have a XGauge on my ScanGauge to give me the temp of the automatic in my truck.

[StrangeWill]

Quick question, not worth another thread...

I got a bumper hitch, I'm looking to rent a 800lb trailer and probably load it with another 600-800lbs. Decently under the tow rating for the bumper (2klbs).

My stepdad wont shut up about buying a hitch. Of course if I buy one I might as well go class 3 and max out the payload capacity rating. Keeps saying I'll hit the brakes, bend the bumper, jackknife, roll, kill half the country, etc.

While 2100 miles may be a bit long, the hitch IS rated for 2000lbs. So being as we have people here who actually tow shit, what is your opinion?


Problem is: I'm leaving in a WEEK. I have to sell my car, get some stuff done, and go to work, so my schedule is stuffed like a bitch, and I don't want to do anything that wouldn't be worth the time. And a lot of review of hitch installers around here seem to complain it's a 5 hour procedure. So it basically screws me out of a day.

[Tups]

What's a bumper hitch? Couldn't find good pics with Google...

edit: Is it something like this?

I see no problem towing a 1600 lbs trailer with that even if it had no brakes of its own as long as the car is rated for it. Just mind the increased braking distance and slower acceleration. 2100 miles is a long journey, but it's not impossible as long as you take care of rest stops, pay attention to how you load the trailer, check that the cargo has not moved between stops etc.

My car is rated for 1000 lbs (brakeless)/1764 lbs (braked) trailer with that kind of hitch, and I've towed 1000+ lbs brakeless loads with it without unexpected problems. Of course the distances have been a lot shorter, but I don't see any reason why I could have not kept going if I had had to...

[theholycow]

What's a bumper hitch? Couldn't find good pics with Google...

edit: Is it something like this?

No, he's talking about this:


Strangewill, if it's rated for that kind of load and was original equipment on your truck, it'll be fine. The bent bumpers you see are from people using improperly installed bumpers or overloading them. Modern step bumpers aren't like they were in 1975...they're thoroughly reinforced to handle their load rating.

Will the height be ok? You don't have any height choices with a step bumper, it is what it is. With a receiver you can install a lift/drop drawbar.

[Tups]

No, he's talking about this

How does that work?

Still, I don't think it's that different from the hitches we have here when it comes to driving and towing.

[comingbackdown]

No, he's talking about this

How does that work?

Still, I don't think it's that different from the hitches we have here when it comes to driving and towing.

Put a hitch ball on it, attach whatever you're towing, drive.