The Nissan Path

I have to start by saying my 2003 Pathfinder has been rocked solid since I bought it. No bad shifts, everything perfect for years, until yesterday.

While driving down a highway around ~70 MPH at about halfway during my trip, my RPMs randomly shoot up. So I slow down and pull over to the side. There seems to be some audible noise when accelerating, but it goes away if I turn overdrive off.

I finish the drive with overdrive off.

I now notice that first gear shifts at 4000-4500 RPM and reverse doesn't work whatsoever, in addition to overdrive not working as mentioned earlier. I'm hearing a slight rattling when overdrive is enabled and i'm driving in first gear. Other gears don't make any noise.

Anyone experiencing anything like this before? Any ideas on what part of transmission would/could affect this 3 things (overdrive, reverse, high shift in first gear) at once?

Thanks in advance.

It doesn't sound good! Low fluid pressure could cause this. Reverse gear requires a lot more line pressure than forward gears, which could explain why some forward gears work and reverse doesn't. This could be caused by a bad pump, stripped teeth inside the torque converter where the shaft engages or by restriction of the "filter" (actually a wire mesh screen), which usually happens when clutch friction plates inside one of the drums start coming apart. If any of those are the problem, you are looking at a transmission overhaul or replacement to fix it. Of course, there is a testing procedure in the factory service manual for your vehicle that can be performed. Low pump pressure can be checked (after confirming the ATF level is not too low, obviously) using transmission oil pressure gauges. BTW, there is also a way to check for stored transmission trouble codes without a scan tool listed in the FSM, which would be the second thing I would check after checking the trans fluid. If the trans fluid smells burnt, is brown in color and/or has metal in it, that's also a sign the the transmission is potentially in need of an overhaul.

Is it possible you've got the dreaded Rad leak where the Transmission lines go through the RAD???

I've read that some of these units have bad radiators in them where the lines of the tranny go through the rad and then you get antifreeze and Transmission fluid mixing together.

NWPathfinder wrote:Is it possible you've got the dreaded Rad leak where the Transmission lines go through the RAD???

I've read that some of these units have bad radiators in them where the lines of the tranny go through the rad and then you get antifreeze and Transmission fluid mixing together.

He has a 2003 Pathfinder, which wasn't affected by the radiator cooler failure issues.

Sorry about that. I missed that.

Still learning.

NWPathfinder wrote:Sorry about that. I missed that.

Still learning.

No worries!

BTW welcome to the Path!!

NWPathfinder wrote:Sorry about that. I missed that.

Still learning.

Easy mistake... The post was in the R51 section. I moved it to the R50 section where it should be.