Uh oh...P0733 code - help

[MxRacer965]

So just got a CPO 2019 Ram 1500 Big Horn 5.7 the other week. It’s been fine until today. I drove it to the airport on Tuesday morning and just got it in today (Friday) to drive home. When I tried to start it the ignition went to ACC instead of starting. I pressed the button again...it went to RUN with no start. I pressed again...OFF. Pressed again and the truck started normal.

Drove through the parking garage, paid, and started leaving...1-2 up shift REV and CLUNK. Weird. 2-3 up shift REV and CLUNK. WTF!? Check engine light and refused to shift out of 3rd...up or down. I pulled into a parking lot, turned off the truck, then started it again. Reverse, no problem. Drive.........no problem now. Drove home including highway at 75 with no issues. Transmission temps normal. Shifting normal. Zero issues.

Got home and put my code reader on it and got P0733, 3rd gear improper ratio.

Cleared code, drove around. No problems.

Any thoughts on this one? I’m not new to FCA vehicles having owned a 2004 Grand Cherokee and a 2011 Grand Cherokee for 10 years but this is my first experience with the 8 speed, so I’m not sure where to start with this other than going to the dealer. I looked to see if there was a dip stick and found none.

Any advice, feedback would be appreciated!

 

[Richard320]

That's a warranty item.

Off the top of my head I'd say a speed sensor in the transmission is giving erratic signals. TCM knows what should be engaged and what the result should be and it's not seeing it.

 

[MxRacer965]

Thanks for the reply!

I was guessing something electronic rather than mechanical based on the fact it didn’t start correctly when I first got in, and shutting the vehicle off and turning it back on solved the issue. Could it maybe be voltage/battery related?

It goes in April 26. Fortunately this is our spare vehicle but I’d still rather not deal with a major issue...

 

[Richard320]

Thanks for the reply!

I was guessing something electronic rather than mechanical based on the fact it didn’t start correctly when I first got in, and shutting the vehicle off and turning it back on solved the issue. Could it maybe be voltage/battery related?

It goes in April 26. Fortunately this is our spare vehicle but I’d still rather not deal with a major issue...

It could be battery related, but that usually lights up the dash with colored lights like it's Christmas.

 

[Fuzznutz]

In the 68rfe behind the cummins that's a death code for the transmission. It means the trans is slipping in 3rd gear. Now with the 68rfe it was usually 5th or 6th, and slipping 3rd don't make a lot of sense to me. It's usually overdrive gears. I don't know nearly as much about these transmissions, but sounds like you'll need to see a dealer if you have warranty. Slipping clutches could be caused by low oil, so maybe check that out. Low line pressure causes weak clamping force, thus slippage occurs. I hope I'm wrong but I hated a similar version of the code for 5th gear in my 68rfe. Good luck.

Sent from my SM-A505U using Tapatalk

 

[Fuzznutz]

I actually just read your first post better. I also think it could of been a weak battery moment after it sat for a few days. Load test the battery. A weak or bad battery does funny things, and like I said above, slipping 3rd gear I don't think is impossible, but don't make much sense. I'm leaning toward weak battery, weird moment.

Sent from my SM-A505U using Tapatalk

 

[MxRacer965]

I need to run to Autozone for a couple things, I may just have them load test the battery. I seem to recall browsing around here a couple people have had some oddities with batteries, drain, etc. My DD is a 19 Expedition Max Platinum and over on those forums I’ve heard they do wonky things with the intelligent entry if voltage gets low, and my old ‘11 Grand Cherokee Summit had the air suspension fail and the dealer had it for several weeks trying to fix it, only to discover they couldn’t calibrate things because the battery.

 

[Conman]

MxRacer, is yours an early build from 2018? Have an early build and just got this code as well. We had the harsh shifting since new and we had the TSB software flash done last year which seemed to reduce, but not eliminate the harsh shifting. I've noticed it's felt to shift harsh again. And like with you, 3rd gear shift was harsh, then the CE light went off today. After a few key cycles, the light went out. Shifting fine but plan to take into the dealer to get checked out. This is our daily driver and have not had battery or starting issues. I did not clear the code so the dealer can see the stored codes.

 

[MxRacer965]

MxRacer, is yours an early build from 2018? Have an early build and just got this code as well. We had the harsh shifting since new and we had the TSB software flash done last year which seemed to reduce, but not eliminate the harsh shifting. I've noticed it's felt to shift harsh again. And like with you, 3rd gear shift was harsh, then the CE light went off today. After a few key cycles, the light went out. Shifting fine but plan to take into the dealer to get checked out. This is our daily driver and have not had battery or starting issues. I did not clear the code so the dealer can see the stored codes.

Just checked. Mine is 6/2018. So it must have been a suuuuper early build.

 

[MxRacer965]

Dealer looked at my truck this week for a variety of items. Transmission tech found no codes (I cleared it but didn’t know if there was anything stored permanently), and found it working normal. No issues found.

Yesterday I was leaving the track and it acted up again. Acted like it hit neutral in between shift from 2-3 then when it tried to shift from 3-4. It just stayed in 3. As I was coasting I put it in neutral then carefully back into Drive. Still didn’t want to shift. Check engine light popped on. Stopped. **** truck off. Started it again and it drove fine after that. Checked code when I got home. P0733 again. This time I’m leaving it so the trans guy sees it.

I googled and nobody seems to have reported anything like this…and possible resolutions are all over the place. It sure seems electronic to me if I restart of the truck solves it. Almost like some control modules aren’t “in sync”…

Anyone got any suggested places to bounce these behaviors off of out there on the interwebz?

 

[MxRacer965]

Oh…one thought I had…could this perhaps be a difference in driving behavior between the previous owner and myself? I don’t generally have my foot in the gas too heavily, especially when I have a load in the back and the tailgate is down! Both times this happened I was very gently accelerating. The truck certainly is happy to rev if I put my foot into it more, so it sorta “begs” to be driven harder than I drive it. Sorta wondering if the “learned behavior” of the vehicle and my driving style “confuse” it?

 

[Conman]

Oh…one thought I had…could this perhaps be a difference in driving behavior between the previous owner and myself? I don’t generally have my foot in the gas too heavily, especially when I have a load in the back and the tailgate is down! Both times this happened I was very gently accelerating. The truck certainly is happy to rev if I put my foot into it more, so it sorta “begs” to be driven harder than I drive it. Sorta wondering if the “learned behavior” of the vehicle and my driving style “confuse” it?

Did you get this resolved? Dealer was no help to me on this so gave up and traded the truck for another brand since the trade-in values on used trucks are soo high. Loved the RAM, but the dealer experience dragged it down.

 

[MxRacer965]

Did you get this resolved? Dealer was no help to me on this so gave up and traded the truck for another brand since the trade-in values on used trucks are soo high. Loved the RAM, but the dealer experience dragged it down.

Yes, fully resolved. Dealer put in a whole new transmission. Ram paid for it all 100% under the power train warranty. Working fine since. I haven’t put many miles on it though, it’s just our spare vehicle/toy hauler.

 

[XDBrad]

Same code and similar symptoms here (also a 2018 build), only slips between 3rd and 4th and only when it's cold. Dealer has had it for a week waiting on a new transmission and frustrated as they don't have a loaner or rental available, and RAM customer (doesn't) care hasn't been much help either. Maybe another week... maybe time to take advantage on the used value and trade for something with dealer support.

 

[XDBrad]

12/8/21 update… dealer still has the truck and has the new transmission in hand. However, RAM is giving them the runaround on approving the repair. First they wanted details of the synchro failure, then wanted pictures, now wants detailed information on the labor required to remove/replace the transmission. I called the service rep on this thinking you can’t make this crap up - only to be shown the communication chain on the computer. What a goat rope! Part of the problem is that the dealer wants to replace vs rebuild as they have had too many trucks returning after a rebuild. Obviously RAM only wants to rebuild. I have an open case with FCA but they admit they aren’t in the approval chain and can’t help.
I’ve never questioned the RAM since day one and don’t today but I sure question FCA and am seriously considering swapping back to a three letter brand or maybe even the blue oval. Neither of these brands are any better built but I’m not hearing of corporate stalling on warranty claims.

 

[MxRacer965]

12/8/21 update… dealer still has the truck and has the new transmission in hand. However, RAM is giving them the runaround on approving the repair. First they wanted details of the synchro failure, then wanted pictures, now wants detailed information on the labor required to remove/replace the transmission. I called the service rep on this thinking you can’t make this crap up - only to be shown the communication chain on the computer. What a goat rope! Part of the problem is that the dealer wants to replace vs rebuild as they have had too many trucks returning after a rebuild. Obviously RAM only wants to rebuild. I have an open case with FCA but they admit they aren’t in the approval chain and can’t help.
I’ve never questioned the RAM since day one and don’t today but I sure question FCA and am seriously considering swapping back to a three letter brand or maybe even the blue oval. Neither of these brands are any better built but I’m not hearing of corporate stalling on warranty claims.

Weird. I got a whole new transmission. No runaround or anything. First they were thinking about valve body but when the tech got into it and found burnt fluid and debris they authorized a new trans immediately.

 

[Andrew0429]

12/8/21 update… dealer still has the truck and has the new transmission in hand. However, RAM is giving them the runaround on approving the repair. First they wanted details of the synchro failure, then wanted pictures, now wants detailed information on the labor required to remove/replace the transmission. I called the service rep on this thinking you can’t make this crap up - only to be shown the communication chain on the computer. What a goat rope! Part of the problem is that the dealer wants to replace vs rebuild as they have had too many trucks returning after a rebuild. Obviously RAM only wants to rebuild. I have an open case with FCA but they admit they aren’t in the approval chain and can’t help.
I’ve never questioned the RAM since day one and don’t today but I sure question FCA and am seriously considering swapping back to a three letter brand or maybe even the blue oval. Neither of these brands are any better built but I’m not hearing of corporate stalling on warranty claims.

Did you ever have a conclusion from your RAM dealer? I just purchased a 2020 with 12,830 miles, drove 45 miles and am experiencing the same issue. Did they end up replacing your transmission? If so any further issues? Thank you!

 

[Andrew0429]

Just heard back from my service advisor this week, apparently the valve body was already changed at 9k miles for the same issue, since that has already been done, RAM has authorized the new transmission under warranty. They’re estimating around 2 weeks to get the transmission delivered. Hoping it’s no longer than that.

 

[Phantom_h60]

Just brought my 2020 1500 (18,800 miles) in for the same. They didn't give me the code but said it was improper ratio. They didn't have any techs in on a Sat so I have to go back this Wed. It all started when I left my driveway and it wouldn't shift and the CEL popped on. I stopped and restarted and it started working again. I'm hoping it's not a trans replacement. Dealer cleared the code and so far it hasn't come back. So far this is my only big issue. There is an annoying vibration from time to time just before the truck stops while braking I might have them address.

 

[2022Tradesman]

Just brought my 2020 1500 (18,800 miles) in for the same. They didn't give me the code but said it was improper ratio. They didn't have any techs in on a Sat so I have to go back this Wed. It all started when I left my driveway and it wouldn't shift and the CEL popped on. I stopped and restarted and it started working again. I'm hoping it's not a trans replacement. Dealer cleared the code and so far it hasn't come back. So far this is my only big issue. There is an annoying vibration from time to time just before the truck stops while braking I might have them address.

That sounds like what I have in my 2018 build when stopping also. Let me know what they say about it. It only happens when slowing down around 10-15mph(20kmh) and couldn’t recreate it. No codes yet despite a couple hard shifts.