Drive train problems
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Joined: Nov 2014
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From: Beaumont, Texas
Drive train problems
so here is a little back ground I have a 2015 f150 4x4 crew cab with the 3.5 ecoboost. So I was driving home last night on the interstate at about 75-80 mph and all of the sudden my truck lost power I mean complete power to the drive train. The motor does respond to throttle as in revving up and rpm does go up as you would expect. But when you put the truck in gear and give it throttle the truck does not move at all, there is no grinding noises what so ever. So I get my code scanner and the truck does not have any codes to read other than a wrench shows up on the dash and says see owners manual. Has anybody has this happen to them? By the way the truck only has 49,500 miles on it. Any and all help appreciated
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Joined: Nov 2014
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From: Beaumont, Texas
Yeah that’s what I was thinking but I would have thought I would have heard something. Once I pulled over I got under the truck and tried to manually rotate the driveshaft and it felt good and tight like nothing was wrong. I am thinking it is something electrical. First I thought it may have been going into limp mode but from further research limp mode you can still drive just max speed of like 15-20 mph
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so here is a little back ground I have a 2015 f150 4x4 crew cab with the 3.5 ecoboost. So I was driving home last night on the interstate at about 75-80 mph and all of the sudden my truck lost power I mean complete power to the drive train. The motor does respond to throttle as in revving up and rpm does go up as you would expect. But when you put the truck in gear and give it throttle the truck does not move at all, there is no grinding noises what so ever. So I get my code scanner and the truck does not have any codes to read other than a wrench shows up on the dash and says see owners manual. Has anybody has this happen to them? By the way the truck only has 49,500 miles on it. Any and all help appreciated
Thread Starter
Senior Member
Joined: Nov 2014
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From: Beaumont, Texas
I think it could possibly be a code that can’t be read with it. From what I understand it can only reach the ECM and see those codes. I would bet the code is in the tcm or something like that. If I remember right when I was looking at forscan I could see in those modules so maybe I will try that and see if I can find one.
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Joined: Nov 2014
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From: Beaumont, Texas
well it appears to have the code PO731 which is referred to Gear 1 incorrect ratio. I had to use my obdlink scantool and forscan to find this code since it was inside a module and not just the ecm. Anybody had to deal with this? I will be more than likely taking it into my local for dealer and having them look at it.
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Joined: Oct 2015
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From: Middle Tennessee
Best guess, but only a guess. You lost a sensor in the transmission. There should be an output shaft speed sensor. The ECM expects to see it spinning at a certain RPM in relation to what gear you are in, engine RPM and torque converter lockup status.
Your code suggests that the output shaft speed does not jive with the inputs. Either a failed sensor, transmission hard parts failure (maybe pump?) or total torque converter failure.
Disclaimer... I'm not an auto trans expert... I'm not intimately familiar with the specific electronics at play within the 6R80
Your code suggests that the output shaft speed does not jive with the inputs. Either a failed sensor, transmission hard parts failure (maybe pump?) or total torque converter failure.
Disclaimer... I'm not an auto trans expert... I'm not intimately familiar with the specific electronics at play within the 6R80
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Joined: Mar 2016
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From: Newnan, GA
I had same thing happen 3 or 4 times in my '05 5.4L truck. It was a bad design TPS on the TB. Shutting truck down and restarting it cleared the problem for that drive cycle anyway. Orange wrench light would appear on dash. Maybe this doesn't apply to '15's?