Hi, back again. I have a 2001 DRV 3500 5.9L maxi. While highway driving w/cruise control on a very slight uphill grade caused the tranny to uncharacteristically downshift. The "overdrive off" light popped on and I can't get it to go off. My OBD reader threw code P1740 and found this description for it on the internet;

""The P1740 code will set if expected RPM drop is not achieved while attempting to engine TCC and/or Overdrive. The P1740 code indicates malfunctioning torque converter or overdrive clutch.""

OK so I have a good idea what the problem is but can I continue to drive the vehicle without overdrive and not screw up the transmission or engine? I know I'll get worse gas mileage and would slow my cruising speed down to at or under 60.

Thanks

 

Just disable overdrive manually. You can drive that way for a while, assuming there isn't anything mechanical causing it...... I would have a look at the wiring, see if anything obvious presents itself.

 

Sometimes, and more so in 4-speeds, OD is the first gear to go bad.
The clutch is probably worn out. The torque converters are known to go bad too. I would pull the pan and make sure you don't have metal fakes in the pan. If you don't, then you could run it without OD for a long time. Well as long as the other clutches hold out

 

thanks for the response. When you say "for a while" I'm really not sure what that means. Like a half hour or weeks?

Thing is because of this virus exploding i have to get to CA 2,200 miles away fast. Best repair estimate I've gotten is one week. If my problem just means I have no O/D and my mileage will drop and the higher rpms will wear the engine faster I don't care. I drove 200 miles today with O/D switched off and no problems. If I can go 200 miles OK shouldn't I have a good shot at 2,000 or is there something I'm not getting?

 

It depends on what is wrong. If it's a mechanical problem, then the more ya drive it, the greater the danger of something failing. If its just wiring, or a solenoid, no big deal. Its a crap shoot. Not sure I would trust it to drive cross country.....

 

Thanks for response. Problem diagnosed as leaking seals. Shop advised they couldn't give me a price w/out opening the tranny and it could go so high I should consider a rebuilt tranny for 3 to 5 grand instead. That's not a possibility at this time and I'm down to my last question. I need only one more long highway drive out of this van. Mechanic says I'm good to go in the other gears w/out O/D which I've sorta confirmed with a few hundred miles already successful. Mechanic suggested top speed of 50 but is sometimes the min speed limit. Should there really be much of a difference 55 instead of 50. I'm just making this one last long run. Thanks

 

The trans isn't going to care how fast you are going. It'll either fail, or it won't. 50, 55, 60, just doesn't matter. Just keep engine RPM reasonable, see what happens.

That said, 3 to 5 grand for a rebuilt trans??? That's insane. I can get one rebuilt, including remove/install for less than 2K around here. You could buy a mega-viper for around 2500...... couple hundred more for R&R.... still under 3K....

 

im in S. Fl and mechanics get you.
I'd do it for 2K. Thanks

 

Rebuilds are weird. Im not a tranny expert, but I did stay at a Ford dealer for 4 long years
There is basically Level 1-2-3. The higher the level, the more work.
Level one is basically seals and clutches.
A level two would be those above, plus a torque converter and other smaller seals in the valve body.
A level 3 is a total rebuild with everything above, plus all seals, and maybe even a new valve body and front pump ($$$).
Ive had a level two done when I had my 32rh and it was 2k. Totally worth it since the guy who did it was a wiz with Torqueflites. This was 10 years ago and when I was back in Florida.
I would suspect 2-2500 would be a level 1 today.
3k would be a level 2 and 5k -- well - that is high. A level 3 should be less than 4k.
That is what I would suspect. Just last month it cost me $500 for one new temp sensor, a fluid change and TCM programming. FWIW I had the 3.9/32RH swapped for a cleaned up 360 and level one rebuild of a 46RH and that set me back 6k.
There are 1000s of used trannys out in the boneyards. Swapping a used one in is a real possibilities on the cheap.

 

thanks very much for the info. The "boneyard" sounds like the way to go. I've only got 91K miles on the engine which runs great. Questions- Does a junkyard normally remove their tranny? There's no way I could. Also once you get it who would install it? I know the mechanic I like to use wouldn't because he's told me that about other parts. Even when I purchase brand new unopened and higher grade parts (eg. Moog) he won't warrantee them.

Anyway i I appreciate all the advise I received about this because even though I didn't fix the overdrive I've gotten enough info to at least "feel" fairly good about this long trip I have really no choice but to make. I'm 700 miles in now w/no O/D and no problems. At the end of this trip I won't even use O/D in hilly urban CA. I turn O/D off each start up but with the shop manual will figure out what wire to cut or fuse/breaker to pull.
Thanks