A newbie requesting info on towing

[Sunbeam]

Sunbeam,

I have rebuilt a number of auto trannies (and other parts) when I worked in a 4x4 shop in Spokane. As you noted, too much heat does them in very quickly. Just remember, your temp gauge measures the average heat of the transmission and measured by the temperature of the fluid. Some parts of your transmission are running far hotter than you think. Some far cooler. Just how hot? That is tough to tell. If it were too hot, it would have already had a major failure. Keeping cool, clean fuild in it will greatly extent the life of the transmission. I change mine every year in my E-450 V10 motorhome.

Thanks for your thoughts. I mostly see what you mean, although if the "hotter" parts have transmission fluid circulating around them (and I would hope they would, although maybe not?) then it seems like it would be reflected in the fluid temperature, especially over hours and days of towing (?) Good point on changing the fluid; I have done that regularly in my car and will do so in the van as well.

Trucks have ratings for a reason and if you are within the parameters, the truck/van will be fine, at least safety wise. Longevity wise, well that is another topic entirely as anytime you increase the load you increase the heat. And in doing so, reduce the longevity of the components doing the work. How much? Again, that is hard to measure, but probably not too significantly if you are in the middle of the GVCW bell curve.

I suppose another consideration, beyond a simple statement to "not go over 75% of rating" is where the weights lie. For example, my van is already at about 58% of its GCWR before I hitch anything up to it. In other words, the mass of the van is a good part of the overall percentage of my GCWR, and the boat and trailer a much smaller percentage. Maybe that means that a "flat" percentage statement is not always as accurate as it could be.

Naturally the higher rated vehicle will always be taxed less than a lower one, but for many people there are other factors that lead them to a certain vehicle (maybe they don't tow often, or they need a certain type of vehicle for daily use, etc.).

Since my van started out with 100,000 miles of no towing ever, I'm hoping I can play a bit of "catch up" without any undue wear on the transmission surpassing just the general mileage wear of the overall unit. I appreciate your fleshing out the earlier statement (made by someone else, not you) a bit.

Sunbeam

 

[Sea Wolf]

Sunbeam-

My statements are generalizations derived from the many threads on this same topic/theme that occurs every couple of months here on this site.

However, they are not exact, and quantifiable predictions based on scientific testing and measurements.

Still, your questions are very valid!

Without being an expert, I will still offer some comments.

First of all, the temperature gauge for the transmission is a single device and is placed at single measurement point, wherever that is.

It does not measure higher or lower temperatures at each transmission band, bearing, valve, seal, gasket, or at the torque converter, only the overall temperature combination.

Thus hot spots cannot be detected, if they exist. It would be interesting to see if the automotive engineering folks have studied temperature variations within an automatic transmission and how much they vary. (?!?) (I'm sure they have!)

Does your transmission exhibit hot spots of heavier than normal wear when towing? Who knows? We have no data.

And yes, a I agree, abnormal wear should (usually) show up as friction and the associated high wear hot spots. Also, we should keep in mind that high general transmission fluid temperatures should also reduce lubrication throughout the transmission, especially as the fluid ages from repeated usage/mileage.

Your temperature ranges seem perfectly fine within what we can assume to be normal limits, but I am unaware of what those exactly are. Another guessing game!

If I thought I was going to be pushing it with a tow vehicle with an automatic transmission, I would get a radiator with more rows of cooling elements and a larger transmission heat exchange tank at the bottom. Additionally, it probably would be possible to add a secondary transmission heat radiating element and electric fan, but that would constitute an extreme adaptation/modification.

Just my thoughts on the topic, in general.

Joe. :teeth :thup

 

[Sunbeam]

If I thought I was going to be pushing it with a tow vehicle with an automatic transmission, I would get a radiator with more rows of cooling elements and a larger transmission heat exchange tank at the bottom. Additionally, it probably would be possible to add a secondary transmission heat radiating element and electric fan, but that would constitute an extreme adaptation/modification.

Maybe I'm thinking of something different than you are describing, but I did put an (additional) transmission cooler on my car, with which I occasionally tow a small trailer. It was a pretty easy mod (they make "over the counter" coolers so I didn't have to engineer anything). No separate fan though.

I thought I would look into getting one for the van, but so far the fluid temperature seems to stay within reason, presuming all of the wear parts are immersed in it (I understand manual transmissions; automatics are sort of "mystery boxes" in my mind).

When I poked around on some forums about my transmission, looking for some numbers, there were "4x4/extreme folks" discussing it, some of whom had worked in transmission shops. From that I got two different figures (to keep it below in order to avoid premature failure), so who knows, but one said up to 250º and the other one said to keep it below 200º. Since I would just about have a heart attack if it got anywhere near that (!), and since I have only very occasionally got it up to the low 180's (top of steep pass), I did relax a little bit.

I also thought it was interesting that an F-350/V-10/dualie that's rated to tow a LOT also got up its TFT into the 170º's when towing a 4,000# boat -- which would have been well under 75% of the GCWR. Before measuring the TFT, I was wondering if maybe such an unloaded-yet-tough vehicle would run a lot cooler. It did run a bit cooler than my van, but not much. One difference though: I don't run my van in overdrive when towing, except for very occasional "easy" situations - this helps to keep it running cool. With the "house mover" F-350, towing in overdrive was much more feasible.

Like you say though, it's hard to know for SURE without cracking it open. I guess I just wanted to understand whether the transmission could "secretly" be damaging itself while appearing to be cool as a cucumber. One thing I don't totally "get" (but like I said I don't really understand automatics like I do manuals) is that, if one part of the transmission is running "hot," and that part is immersed in the transmission fluid, then wouldn't I see evidence of that by the overall fluid temperature going up? That's just my "uninformed" logic asking, thinking of, say, putting a 250º stone in a jug of 150º water. (Mind you, I'm not expecting anyone here to completely guarantee the life of my transmission.)

One thing I will look into is the fluid itself. Maybe there are some numbers on how hot it can get without the cooling/lubricating value being compromised, and/or perhaps there are specific fluids that work better in that regard.

Sunbeam :hot

PS: Just as a point of interest, on the same vehicle the water temp basically doesn't change. Runs at about 205º not towing, and around 206º towing. Hmm, writing that, I wonder what the engine oil temperature runs at. Seems like that might be over 200º routinely (if it's near the same as the "water" temp....?). Yeah, I'm a data-nerd :scurries off to find out the ratings on transmission fluid: (well, it is a cold, nasty day here, so why not?)

PPS: I haven't gone nuts fact-checking, but this article looks reasonable and has a few numbers. They say that every 20ºF increase over about 175º halves the life of the transmission fluid (OTOH, they say that most transmission fluids are designed to run "indefinitely" at 175º). Here is a link if anyone cares to read it.

http://autos.yahoo.com/maintain/repairqa/transmission/ques123_0.html

Now I have to get off the computer and go work on my water tank installation (even though the weather makes spending the afternoon researching transmission fluid look somewhat more appealing!)

 

[Will-C]

A truck camper plus towing a 22'25' boat I would recommend a new one ton 4x4 Chevy with an extended cab and an eight foot bed. Nice trucks and with the Duramax diesel you get 660 plus foot pounds of torque. Engine braking is a plus they hold their value pretty well and are fun to drive. The longer trucks will track better plus with the Duramax diesel you get a proven Allison six speed transmission. No strap on transmission coolers required. If your going to stay close to the front porch you can get by with less. We have a few friends who tow a 27' Ranger tugs with this same truck effortlessly. One is a GMC (a Chevy with lock washers) but both are road warriors and are very happy with the complete Duramax truck package.
D.D.

 

[potter water]

One more time, some numbers from my half ton V8 Dodge, my three quarter ton V10 Dodge and my three quarter ton Diesel Dodge. All numbers are at average cruise of 65 MPH with little city driving, though I have some city driving numbers as well. All three trucks are 4wd crew or extended cab 4 doors.

V8: Highway no tow, light load-17mpg
Highway towing 6000 lbs. 8 mpg
City driving-13 mpg

Special Note: Often in second gear on typical passes, and occasionally into first gear for steep grades on secondary highways. Loosy goosy in cross winds. Scary towing and emergency stopping...dodging stuff on the road.

V10: Highway, no tow, light load-17mpg
Highway towing 6000 lbs.-10 mpg
City driving 14 mpg.

Special Note: Frequent second gear, never in first gear on passes. Excellent control in cross winds. Often in third gear out of overdrive when towing. Good in emergency stopping, dodging stuff on the road etc.

Diesel: Highway no tow, light load-20 mpg
Highway towing 6000 lbs.-14 mpg
City driving-18 mpg

Special note: Excellent in cross winds and emergency stopping. Seldom out of over drive but frequently in third gear on passes on interstates and secondary roads.

These are similar 6000 lb loads, always a boat. Fifth Wheel towing, though not a lot heavier will knock another MPG off all the numbers. All are measured and calculated fill to fill over 50000 miles, each truck and over 90000 miles on the diesel.

I've said it before, and I'll say it again. The difference in diesel mileage comes very close to making up the difference in gas versus diesel prices and they are so much more relaxing hauling a load over long distances.

But, to each his own. I don't think there is a percent difference between similar truck sizes and engines or fuel when comparing ford, chev, or dodge, so pick your favorite brand.

 

[Captains Cat]

V10: Highway, no tow, light load-17mpg
Highway towing 6000 lbs.-10 mpg
City driving 14 mpg.

Harry, never got that with my Dodge 2500 V-10. Best I could do was abt 13 highway, 12 city, 8 towing 12000# tomcat. If I'd have done that well, would probably still have it. Maybe the 4wd made the difference?

Charlie

 

[localboy]

Why not eliminate the camper and use the boat for both needs? Put a canopy on the bed and you can store a small ladder, bags, equipment etc with some measure of security. That's the way we'd go and we pull w/ a F250.

 

[kennharriet]

We have an 07 Silverado 2500 with the Duramax/Allison. We leave a cab over Alaskan camper on it all the time and pull a 12,000 lb. horse trailer. It handles the 22' Cdory effortlessly, including emergency braking. A diesel is certainly more costly for routine maintenance. At least for our vintage truck, the only difference between the 2500 and 3500 is one rear leaf spring. Otherwise it is the identical truck.

I also agree that Ford, Dodge and GM deisels are high quality and a matter of preference.

 

[Sunbeam]

I've said it before, and I'll say it again. The difference in diesel mileage comes very close to making up the difference in gas versus diesel prices and they are so much more relaxing hauling a load over long distances.

Are you talking strictly of fuel prices, in your "difference in prices"? Because another factor is the price of buying the vehicle - maybe you factored that in, but it was hard for me to tell from the way you wrote it.

This is a non-towing example, but before I bought my C-Dory, I was considering a Sprinter van. They're diesel and so get better mileage than a typical gas-powered van. That was all sounding really good until I factored in the cost of the vehicle itself. (There was more to the decision than this, but I'm just isolating this at the moment.)

I'm not saying that diesel is not great, nor that people should not buy a diesel vehicle - they certainly have advantages, and it's not all about money. Just that when I did the calculations, it would have taken a looooong time to make up the difference in purchase price with the better mileage. Especially since the diesel "profit" is only the difference in mileage between the two (also subtracting the fuel price difference).

Maybe this is different for different types of vehicles; I was only looking at vans, so didn't check on, say, the difference in purchase price between a Ford F-250 diesel and a Ford F-250 gas.

Sunbeam

 

[Captains Cat]

To say nothing about engine noise too. The reason I had a gas v-10 and not a diesel in my 2000 Dodge 2500 was that I couldn't hear the radio in the diesel version. A lot quieter now though!

Charlie

 

[journey on]

Well, for your first post, there's a lot of answers/suggestions. And I'm not going to get in the truck argument, just make a few suggestions. How's that for weasel wording?

Earlier, someone made a very important point (OK, it was Bob/thataway,) and it appears to have slid right by. So I'm going to empathize it.

Those of us that tow cross country, use the C-Dory as a RV.

Here's Journey On up in Lake Superior in a RV park:

Or on Vancouver Isle:

We have done this for years and it's worked well. Just tell them you have a 22/25 RV and they're happy. Well, we were rejected once in Campbell River, BC, but we left and found the Indian RV Park right on the Inside Passage. That was one of the bast views we ever had, sitting in the cockpit and watching everything going up and down, just a couple of hundred feet in front of us. We weren't locked in a camper, right?

So, you're buying a C-Dory because you can live on it and then you want a camper? Up to you, of course, but just spend a moment thinking of the simplicity, easier towing and cost.

Boris

 

[Sea Wolf]

Boris-

Good point!

Forget the Camper and use the CD instead, and use the money you saved on not buying the RV to upgrade your tow vehicle from a:

1/2 ton to a 3/4, or

a 3/4 to a 1-T, or

a 1-T to a 1-1/2-T (F-350 to F-450)

Or how about a F-550, F-650, or Freightliner, Mack, Peterbuilt, etc.? :lol:

Plenty of truck in there somewhere! :smiled

Joe. :teeth :thup

 

[kennharriet]

IMHO, a diesel will cost more overall considering purchase price and routine maintenance (lubrication, filters, etc.). If you are planning to travel a lot with your Cdory or other loads, a diesel is probably a better long term investment. If you are only planning on short trips to the marina or limited long distance mountainous travel, a gas rig is certainly more cost effective. All of the components of a diesel truck are stronger and longer lasting (engine, drive train, etc.)

We purchased a diesel as a long term investment because we intend it to be the last tow vehicle we buy. It is probably the only new vehicle we will ever own. It is our retirement RV. It is more comfortable to drive than a luxury sedan, even with a heavy load in tow.

If you plan to horse heavy loads around the country, the heavy duty components of a diesel vehicle will provide greater longevity and safety. A gas tow vehicle is the best choice for many. Maybe the real question is: what will allow you to spend the maximum amount of time on the water.

 

[Sunbeam]

To say nothing about engine noise too. The reason I had a gas v-10 and not a diesel in my 2000 Dodge 2500 was that I couldn't hear the radio in the diesel version. A lot quieter now though!

That was one of my thoughts with the van (after I had ruled out Sprinters, then I still had diesel and non-diesel Ford vans to consider). Given the way the engine is right next to you in a van, I figured the diesel might be a shade loud!

I have read that the newer pickups with diesels are pretty quiet, but I have not compared the two myself.

 

[Captains Cat]

To say nothing about engine noise too. The reason I had a gas v-10 and not a diesel in my 2000 Dodge 2500 was that I couldn't hear the radio in the diesel version. A lot quieter now though!

I have read that the newer pickups with diesels are pretty quiet, but I have not compared the two myself.

They are. I'd buy one today but with the 7.3 L Excursion, I don't need to... :thup :wink:

Charlie

 

[journey on]

OK, I can't resist in this free-for-all.

We (actually Judy,) bought a new truck to haul Journey On, our C-Dory. Here are some truisms about Ford trucks. I'm pretty sure other brands are similar.

1. Ford (dorf?) says that the gas V-8 has the same 5 speed trans a diesel would have. With that transmission, the gas V-8 has all the power you need to haul a C-Dory. Just pull the lever to shift down and go up the hill. And keep it in the same gear to go down the hill.
2. Ford trucks have sturdier axles based on their series/weight rating (3/4 ton, F-250; 1 ton, F350) not their engine rating. Diesels get the same rear axles.
3. The simpler the truck, the more it can haul/tow. That's because larger engines, bigger, fancier cabs, 4 wheel drive all weigh more and the truck series (F-250, F-350) each have a fixed maximum weight. Put in a bigger engine, it weighs more, it has to haul less. Double cabs weigh more, it has to haul less. Reflected in the Ford specifications on hauling/towing.
4. Duallies have poor traction when they're lightly loaded. If you're using one to haul a boat, make sure you have a lot of weight in the truck bed. Camper, sand or cement. In the F-250, I can't use a leveling hitch or the rear wheel slip when going up a hill ( such as a launch ramp,) and I don't even have dual rear wheels. The more tyres one puts in the rear, the less loaded each one is and the poorer traction (up to a point.)
5. If you buy a C-25 or a Tomcat, invest in electric/hydraulic disk trailer brakes. I don't care how big the truck is,one needs good brakes on the trailer.

And a merry Epiphany, Boris

 

[Chester]

Consider the cost of oil change$ when looking at diesel too.
Prior driving experience factors into tow rig size. I used to drive truck and am comfortable with a smaller, though capable, tow vehicle than some other folks.

 

[potter water]

I bought my 2006 diesel 2500 Dodge used in 2008 for 26000.00 with 45000 thousand miles on it. It is the standard interior and a basic 4door short bed. The model is Big Horn, so it is trimmed out decently. The new 2008 gas version, don't remember if they had the V10 or Hemi as their BIG gas engine, was about 30,000.00. Of course, the cummins small truck diesel is just broken in at that mileage and is normally expected, with proper maintenance to not need overhaul for several hundreds of thousands of miles. It will certainly outlast the rest of my driving life.

So, diesels, are probably the best cost per mile over time vehicle. There is a lot of evidence to support that as you will invariably see diesel UPS trucks racking up gazillions of miles...they are diesel because of operating cost per mile. Same with almost all other high miles commercial users, inter city bus, and so on. So, I think the cost per mile issue is sealed. BUT that cost per mile is recovered over lots of year and lots of miles. You won't get the lowest cost per mile if you have to have the latest truck every couple years!

Regarding noise, even my 2006 is noisy on the outside, but is easy conversation quiet on the inside. It is no more uncomfortable noise wise than my V10 gas was. (A big louder, but not enough to bother).

Maintenance is key for any engine. My diesel oil changes at the jiffy lube are about 74 bucks, but I only do 4 of those a year. Of course, if an engine looses a piston, or a block is cracked, or the trubo fails, then you are talking bigger dollars for repair than gas. But, in the case of the dodge, the engine parts count is much smaller than the equivalent ford or chev, and piston size and rod heft is much larger so I'm thinking the probability of a major costly failure with the diesel is smaller than the equivalent gas engine.

I've driven probably a million and a half miles and have practiced MPG management in all my driving. (After my dad stopped paying for my driving 52 years ago)! Keep it at 65 or below. Be as light as possible regardless of tow or no tow. Use the gears to advantage. Slow starts from full stop. Only push the pedal to the metal in emergencies. Tire pressure management makes a big difference in trucks. And so on.

I think that wears out all my thoughts on trucks. Gas or Diesel, I love driving a truck and so does my wife. Up high where you can see the world go by.

 

[Captains Cat]

Maintenance is key for any engine. My diesel oil changes at the jiffy lube are about 74 bucks, but I only do 4 of those a year. Of course, if an engine looses a piston, or a block is cracked, or the trubo fails, then you are talking bigger dollars for repair than gas. But, in the case of the dodge, the engine parts count is much smaller than the equivalent ford or chev, and piston size and rod heft is much larger so I'm thinking the probability of a major costly failure with the diesel is smaller than the equivalent gas engine.

Not sure about "parts count". Never took it apart to count'em... :disgust

The 7.3L holds 15 quarts of oil and I haven't changed it myself yet but had it done for me 2x. I started to do it once but discovered, just in time, that my oil drain pan only held 3 gallons!

The fuel filter is equally important to pay attention to but that's a simple thing to do.

Charlie

 

[thataway]

Oil changes: Oil is pretty cheap when you look at it in an over all expense. Generally the larger diesels go up to 15,000 miles between oil changes (but so does my wife's new car). If towing or heavy service, then the oil needs to be changed earlier.

I have had two transmissions failures--one was about 55 years ago, using a Dodge sedan to tow about 10,000 lbs across country.

The other was in an RV at about 65,000 miles--and that transmission was way undersized for the RV. Other vehicles, used for tow, I have gone well over 100,000 (and it the case of Charlies's Excursion--it is at 177,000 and on the first transmission)