2006 Pathfinder LE rough shifts/downshifts

The Gas and Diesel Engines - VQ40De, VK56DE, YD25DDTi, V9X, Transmission, Transfer Case, Oil, Differentials, Axles, Exhaust...

Moderator: volvite

Blake2001
Posts: 8
Joined: Mon Jul 18, 2022 6:53 pm

2006 Pathfinder LE rough shifts/downshifts

Postby Blake2001 » Mon Jul 18, 2022 6:54 pm

I drive a 2006 Pathfinder LE (2WD w/o OR package; 154k miles). A few weeks ago, I installed a “new” valve body (used from another 2006 Pathfinder LE). It solved the initial issue I had at hand, but I’ve began noticing some hard gear shifts (particularly downshifts too). I had flushed my ATF during replacing the valve body, so I wondered if I didn’t end up adding enough. I checked my ATF levels yesterday and was definitely low since it had a “cat urine” smell. I added more, and I believe they’re good now (difficult to be certain with how goofy the dipstick is and was scared to potentially overfill it). Anyways, after adding new ATF, it seemed as if I could feel the gear shifts even more than before. What could be the issue here? I didn’t get my TCM reprogrammed upon replacement. I’m now wondering if there could be a correlation there but I don’t have any dash-lights nor codes via my ODB reader. To note, I’ve also noticed that my engine temperature gauge seems to stay on cold for longer than it has before and doesn’t exceed a certain mark (around the 1/3 area) even after driving for 30+ minutes. Anyone have any leads or ideas on this?

(BTW, I don’t have any pink sludge now and didn’t have any prior to needing my valve body replaced.)


User avatar
VStar650CL
Posts: 501
Joined: Wed Dec 09, 2020 6:19 pm

Re: 2006 Pathfinder LE rough shifts/downshifts

Postby VStar650CL » Mon Jul 18, 2022 8:01 pm

There are probably 2~4 different TCM firmware packages for every year of the R51 depending on equipment and options, so there's a good chance firmware is causing at least some of your issues. That won't generally cause codes or dash lights unless you put a 4WD TCM into a 2WD, then the TCM will squawk because it's looking for the AWD Controller. If you get it reprogrammed, make sure the SA notes on the ticket that the TCM should be programmed as a new blank unit using the ROM-ID from FAST, otherwise the Consult3+ will just look for updates of whatever firmware is already in there. Programming it as "new blank" will make sure the repro matches your VIN number.

The varnishy smell in the fluid could be serious if it was way underfilled. More than about 1-1/2 quarts down, things begin to get hot that shouldn't be hot.

I doubt the state of your temp gauge has anything to do with the new VB, unless maybe some wiring got disturbed. Even that seems unlikely, since I'm pretty sure the ECT sensor on your ride is at the top rear of the engine and the ECT signal comes to the cluster on CAN. Most R51's are very consistent running right around halfway up the gauge, so I think I'd assume there's a cooling system issue and diag it accordingly.

User avatar
palmerwmd
Site Admin
Posts: 2343
Joined: Tue Jan 31, 2017 4:45 am
Location: Mid Atlantic

Re: 2006 Pathfinder LE rough shifts/downshifts

Postby palmerwmd » Tue Jul 19, 2022 12:06 am

Welcome Blake!

Blake2001
Posts: 8
Joined: Mon Jul 18, 2022 6:53 pm

Re: 2006 Pathfinder LE rough shifts/downshifts

Postby Blake2001 » Wed Jul 20, 2022 11:46 am

VStar650CL wrote:
Mon Jul 18, 2022 8:01 pm
There are probably 2~4 different TCM firmware packages for every year of the R51 depending on equipment and options, so there's a good chance firmware is causing at least some of your issues. That won't generally cause codes or dash lights unless you put a 4WD TCM into a 2WD, then the TCM will squawk because it's looking for the AWD Controller. If you get it reprogrammed, make sure the SA notes on the ticket that the TCM should be programmed as a new blank unit using the ROM-ID from FAST, otherwise the Consult3+ will just look for updates of whatever firmware is already in there. Programming it as "new blank" will make sure the repro matches your VIN number.

The varnishy smell in the fluid could be serious if it was way underfilled. More than about 1-1/2 quarts down, things begin to get hot that shouldn't be hot.

I doubt the state of your temp gauge has anything to do with the new VB, unless maybe some wiring got disturbed. Even that seems unlikely, since I'm pretty sure the ECT sensor on your ride is at the top rear of the engine and the ECT signal comes to the cluster on CAN. Most R51's are very consistent running right around halfway up the gauge, so I think I'd assume there's a cooling system issue and diag it accordingly.
Thanks for the helpful info there! So, you’re saying a TCM that’s been in a Pathfinder with the 4WD capability function would function different if placed in a Pathfinder that’s only 2WD? How pricey is it to reprogram, and/or would resetting it (via disconnecting the battery for 30 mins, etc.) be capable of “reprogramming” the TCM likewise? Though, if needed to take it to a dealer to have it professionally reprogrammed, any idea on the time/price of that process there?

User avatar
VStar650CL
Posts: 501
Joined: Wed Dec 09, 2020 6:19 pm

Re: 2006 Pathfinder LE rough shifts/downshifts

Postby VStar650CL » Wed Jul 20, 2022 12:29 pm

We get an hour for most ECU repros. They rarely take more than 30 minutes, but only if the Parts Dept doesn't make you stand in line for another half waiting to look up the ROM ID. :wink:

Blake2001
Posts: 8
Joined: Mon Jul 18, 2022 6:53 pm

Re: 2006 Pathfinder LE rough shifts/downshifts

Postby Blake2001 » Wed Jul 20, 2022 1:52 pm

VStar650CL wrote:
Wed Jul 20, 2022 12:29 pm
We get an hour for most ECU repros. They rarely take more than 30 minutes, but only if the Parts Dept doesn't make you stand in line for another half waiting to look up the ROM ID. :wink:
I just talked to my local Nissan dealership’s service department, and the mechanic said that TCM reprogramming isn’t possible for a 2006 Nissan Pathfinder… He said that 2006s don’t need it nor can be reprogrammed? Is this true, or is he just an idiot? Also, is TCM reprogramming a process that only Nissan dealerships/Nissan specialty shops can do? I’m not sure where else to ask for this service at.

User avatar
VStar650CL
Posts: 501
Joined: Wed Dec 09, 2020 6:19 pm

Re: 2006 Pathfinder LE rough shifts/downshifts

Postby VStar650CL » Wed Jul 20, 2022 3:03 pm

Maybe you want to try a trans shop, because that "mechanic" is FOS. The RE5R05A has been CAN-programmable since '04, and there are even aftermarket programmers available so that trans shops and rebuilders don't need to come to me for a repro:
https://www.youtube.com/watch?v=KL8Br1UeQ4E

Blake2001
Posts: 8
Joined: Mon Jul 18, 2022 6:53 pm

Re: 2006 Pathfinder LE rough shifts/downshifts

Postby Blake2001 » Wed Jul 20, 2022 6:38 pm

VStar650CL wrote:
Wed Jul 20, 2022 3:03 pm
Maybe you want to try a trans shop, because that "mechanic" is FOS. The RE5R05A has been CAN-programmable since '04, and there are even aftermarket programmers available so that trans shops and rebuilders don't need to come to me for a repro:
https://www.youtube.com/watch?v=KL8Br1UeQ4E
Not the most fond of trans shops due to my first/initial experience with a local shop...

*Totally off-topic story*
Before I know my valve body needed replacement and took it upon myself to do so, I took my car to a recommended trans shop and they told me "It'll be $4.4K for a rebuild." That's the only info that was received after they did a diagnostic exam of my car. Called a few days later to pursue what real info they gathered. Then they presented myself with a statement saying "Um well it can be fixed with a valve body replacement. We can do that for $2.5K but CANNOT provide a warranty [of any kind]."

Regardless however, I'll try to find a reliable and honest trans shop because I need my TCM to be reprogrammed very soon. Thank you again for your helpful insight and info!


Return to “R51 Engine, Driveline and Powertrain”