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Old 03-02-2013, 08:04 PM
twaunsaint001 twaunsaint001 is offline
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2013 Pathfinder
 
Join Date: Feb 2013
Posts: 3
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Originally Posted by twaunsaint001 View Post
I'm currently repairing a 2001 3.5 Nissan pathfinder 2WD /w no Reverse for a customer.. I test drove the vehicle before i removed the transmission, all gears work fine & shift smoothly except reverse' i got nothing while in reverse not even a noise or attempt.. while in 2nd gear, I dropped to 1st gear, to see if the trans would clutch break, but i didn't get much..

I removed and disassembled the transmissioin all the way down to basic parts; I found no damage , and hardly even any normal wear.. no missing , worn, broken, or unfastened rings.. the condition of all the mechanical parts was like new.. so now i know it's not a mechanical problem.. it's more then likely a solenoid, trans oil pump or a clog..

it's either a presser or electrical problem..
I will be inspecting the transmission pump tomorrow, I already tested the resistance on the solenoids, but I'm unsure if I'm getting true readings, I power tested 2 solenoids one open/close type worked fine on 12+ volts, but the other nothing.. the other 3 solenoids are a differnt type (time pulse modulated) (TPM) i beleve they can only be ohm tested once the transmission is away from the vehicle..

The torque converter cluch solenoid is the only acessable solinoid without having to remove the entire valve body, it's located next to the band servo once you remove the trans oil pan.. the others 4 are locted on the other side (inner side) of the valve body near the tail housing, and they are as follows: the other 4 solenoids are grouped together in a row ,and 3 of them are mounted as a solenoid pack.. the one that is not part of the pack is called the "line presser valve solenoid" it's the only one with 2 wires (+-): the one next to that is "shift solenoid B" and then next to that is "shift solenoid A" and the last one on the end is "overrun clutch valve solenoid"..

Hopefully soon I will find the cause of this problem, and this problem is very common with the 98-2004 pathfinders.. it's pretty clear to me that the transmission don't need to be rebuilt, but what ever the cause is it's small , and well hidden..!! I'll update again when i near the completion of this project..!!



Hey there people's lol.. I have finally finished the transmission project.. Proud to say I have repaired the "no reverse situation.. I ran in to another person needing transmission repairs with a 96 pathfinder with "no reverse while at the Nissan dealer.. I think i'll take a break from auto repair after this one, i'm really a engineer' not a mechanic..!! lol..
well anyway like i said before i found very little damage, and normal wear.. I inspected the transmission pump to find 2 seal rings flattened like pancakes on the trans pump rear hub, that contacts the direct drum, note the arrows on the photo..!!

those 2 rings are plastic "not" rubber o-rings & they were ordered from my local Nissan dealer & shipped from japan, $37.00 each..!! for plastic rings..!! No kidding..!! I also replaced the torque converter clutch solenoid: this solenoid is accessible by just removing the transmission oil pan, and it can be replaced without removing the transmission from the engine.. : Note the circled component on the photo..

I don't think the solenoid was bad ,but the customer wanted it replaced..!! I changed the filter & trans oil, and almost everything i done , except replacing the 2 seal rings can be done by anyone & without removing the transmission.. I think the oil seal rings was the problem, because the oil ports located between those 2 rings was just releasing oil in to the transmission case instead of using it to activate the clutch piston, small parts "big problems..

those rings are made to spin with the drum so it makes sense that overheating & friction together can cause this common problem with these vehicles.. If it's the solenoid that's something to replace before letting someone replace or rebuild your transmission.. even a transmission oil change or filter change can prove helping.. any questions just ask.. hope something i said or done helped someone out there..!! thanks..!!
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