What gear to tow in

[Raspy]

Mike,

I'm certainly not an expert on those Ford C6 (?) trannies, although I had one behind a 6.9 International in a Ford van. It shifted like you'd expect, smooth.

When a new shifting strategy is wanted or during a rebuild, sometimes a modified valve body is installed. This is a typical hop-up strategy and the result is more abrupt shifting. It comes from raising the oil pressure and/or enlarging the oil passages.

Shifting harder does not hurt the tranny, within reason. Shifting slowly (smoothly) causes more wear and heat.

I turned up my old Cummins and overpowered my torque converter. While working on the tranny I adding a stronger TC and changed the valve body. It made the shifting much more abrupt. I ran it for another 180,000 miles after the original 100,000 miles and never had a problem.

On my new Cummins I modified the throttle in a way that gives me more torque down low with the same throttle position, but it's in a way that the tranny doesn't recognize because the trans is simply looking at the RPM and throttle position when it is deciding how hard to shift. This has lead to a slight increase in slipping during shifts at part throttle. Nobody has been able to crack the computer code on the Ram heavy duty automatic transmissions, so I have to be careful with my tuning and not cause more slipping.

[Borrego Dave]

Mike L, a couple buddies had Gear Vendors on their P 30 Chevy MHs, both shifted real....positive . They never had a problem with them or trannys as far as I ever heard. No help to your question, just a comment.

[k0wtz]

I had a Lincoln transmission overhauled one time and the guy talked me into one of those hard shift kits. Never again I hated that car after that it would almost bang into gear not smoooooth like it was before.


Raspy the jury is still out on this ford 6 speed if I didn't have the paddle shifting I would probably get rid of it but I am a gm guy I don't know even why I bought this Edge.


I started with an a-liner camper the 13f scamp is quite a bit heavier and I am being careful with my towing practice. The Edge has that cutting edge styling but the el. were designed by and idiot.


Saying this I don't think this car will go the 450k that my 90 cadilac deville did! no comparison!

[Mike_L]

Thanks Raspy, that makes a lot of sense. My truck was ordered specifically for towing a heavy (~10,000lb) trailer through the mountains, up and down long steep grades and that's pretty much all it has ever been used for. It will shift around 2000rpm. This is where it needs to be when pulling a heavy load?
It has massive torque even at half that rpm so shifting at a lower rpm would also work?
I've never used low range to tow, except to see if it worked, as my trailer isn't very heavy.
It's good to know this won't hurt the tranny.
I haven't done anything to adjust the tranny but was told there is a vacuum line going to a modulator valve that could be used to adjust the shifting. Something about pulling off the vacuum line and using a screw driver to to adjust the screw inside where this line attaches to adjust the shift pattern.
I've been reluctant to do this and now considering your information, I'll leave it alone.
Thanks again. Michael

[k0wtz]

Borrego dave I usually am in shorts and one of those tough looking tank tops and the big belly hanging over my belt. Oh I forgot I also have a huge belt buckle I staple on!!

[k0wtz]

Mike good idea I once camped out in Texas guy hauls in with a big dodge truck of some sort as I talked to him he had spent 3k on a new truck putting different electronic things in it to gain 1 mpg. What nonsense I think those engineers no matter how dumb we think they are do know what they are doing in the long run!

[Mike_L]

Dave, my understanding from the original owner is that low range has the original gearing and high range provides a gear range 30% higher for better fuel mileage when not towing.
Maybe it's the other way around?
I've never used low range, other than to see if it worked.
Changing the range or the gear is always a solid shift.

[k0wtz]

Mike l I had a ford thing once that had all that in it I never turned it on and never needed it but maybe I should have taken it 4 wheeling and destroyed it! I have a 4 wheel drive truck I swear all its good for is to get a person in trouble you know over confident. ever seen that on snow and ice people in the ditch!

[Mike_L]

Bob, a lot of years ago I had a Camero with what to seller told me was a "transmission kit". He called it a "stall speed torque converter". The rpms would go up 500 -600 more than usual before it would shift. The car was wicked fast but not very comfortable and terrible fuel mileage.
Personally, I like a gear box. Then I decide the rpm and when to shift.

[k0wtz]

Mike I own a 1968 eagle bus with a big Detroit 8v71 I read all sorts of posts trying to soup those things up latterly destroying a great motor. Why do people do these things? Yes scarey things can happen I don't think I want to do any shifting anymore I will settle for paddle shifting with my automatic.


if you like it I say good for you but give yourself a few years you will get over all of it and just want to set and relax. I have had all the double clutching experience I want or need for the rest of my life. The shifting part though is fun isn't it try it with a 26,000 lb bus!!

[SilverGhost]

I like out Tiggy (VW) with factory tow wiring. The ESP and trans shifting recognize when a trailer is plugged and change according.

Now the new tug, '78 ScoutII, is another story. 4x4 with Chrysler 727 3 speed. I thought about an OD box, but that gets complicated when its time to 4x4 .

Now I have towed many miles with manual and auto - if you are shifting constantly it is time to pick a gear and just hold it. Figured out through the years there is more danger of engine damage and overheat, on well designed vehicle, than transmission damage. There is more to it than that simple statement, but low RPM/high load will wear hard on engine while forcing A/T to unlock T/C to keep up resulting in heat in trans.

Obvious advise is follow manufacturers advise, is safest bet for us internet advise columns

Jason

[k0wtz]

Jason ever watch or listen how the truckers do things they know how to drop the rpms coming to a big hill to shift and get power to get those 60k loads up the hill and rolling! Listen when they go down the hill to hold the load back they are constantly double clutching down. I got advice from on one time same gear you go up you use same gear going down! Same thing for us whether we use manual or auto but I do not climb hills in od just to hard on the transmission! I do watch transmission temps when tugging also!


later


bob

[SilverGhost]

Bob - ironically my dad was a trucker for many years. He drove slam bangers and bottom dumps most of his driving career, then a little bit of everything when CDL became secondary to his primary job, working in agriculture. I got plenty of practice with the Cummins 350 and Fuller 13 speed around the ranch.

Most of the truckers I see today are under educated and lack experience. There are a few good ones, but they are becoming rare.

Jason

[k0wtz]

Jason yes they are the day of listening for the rpm to hit a gear either up or down are gone. we now have just jockeys! but I love the old pros!!


bob