1999.5 Pathfinder won't shift into drive when cold

[miamicuse]

the AltI have a 1999.5 PF SE Limited with 225,000 miles. Last few months transmission started to act up. When I start the truck in the morning, and I am talking about 95 degrees in South Florida, warm weather cold engine, it will not engage into "D". It will engage into 1, 2 or R instantly without any issue.

Initially I would wait like 5 seconds and it will finally engage. Last few weeks it would not engage even if I wait a minute or two, so I just shift into 2, and drive slower on the local streets. Ten minutes later when I am about to get on the highway I shift into D and no problem. No problem when the engine is hot.

Took it to my mechanic and he said the truck being at this age of 225K it needs a rebuilt transmission and quoted me $3500. He didn't diagnose the problem except to drive it across the parking lot but since the engine was not cold he could not reproduce it. Being that the truck is worth about $1000 at this mileage and age, I have a hard time seeing spending 3K+ on a rebuilt transmission.

Then on searching on the internet I came across a few other folks with similar problems, some on the PF, more seems to be on the Altima. Of particular interest in this thread:

transmission-will-not-go-in-d-when-cold-t551010.html

and especially this post:

"Hello. I have a 2001 Nissan Altima, 163K miles, with the EXACT same problem. Did not go into drive, but would go into reverse, in the morning when cold, and started happening more frequently, but once in gear it ran fine. Changing the trans fluid was a temporary solution, but it started not going into drive again in the mornings. Upon further research, I narrowed my focus to the transmission line pressure solenoid valve that is known to get clogged with debris, and changing fluid alone is not enough to clean it out. The solenoid is accessible by dropping the transmission fluid pan, and as it turns out, there are two small holes of the side of the solenoid. I sprayed carborator cleaner into each hole on the side of the solenoid and black debris poured out for a few seconds and then the carborator cleaner flowed clear. This was a simple fix and has completely solved the problem. A few squirts of carborator cleaner and a transmission fluid change solved the issue - it now goes into gear immediately, and at all temperatures. No need for a new transmission like most of the mechanics were telling me. I hope this helps others who have the same problem."

Would this solution for the Altima be applicable for the PF? Would it be worthwhile to ask my mechanic to change the ATF as well as to flush/clean the transmission line pressure solenoid valve?

Or is it more likely my issue is with the transmission seals and leaks?

Thanks in advance for any advice and comments.

[marioc89]

Well, you pretty much narrowed it down. I'd do a fluid change, not flush, and it wouldn't hurt to drop the pan and check for a clogged solenoid, if we have one.