Transmission troubles

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EvilTheCat
Posts: 59
Joined: Fri Feb 17, 2017 10:03 pm
Location: Lincoln, ne

Transmission troubles

Postby EvilTheCat » Mon Jul 17, 2017 9:08 am

I have had my 2006 SE for about 7 months now. It has given me so many problems I don't even want to list them. I am now possibly facing a transmission replacement but I figured I'd consult you guys before taking it in. I have never liked automatic transmissions and this one is no different.

About a month ago when my wife was driving my truck the tranny started acting weird. Kind of like it was stuck in a high gear. We stopped and I tried driving it, but after I restarted the truck it shifted normal. A day later the same thing happened. After some research I found out that these trucks have what is called a "limp mode." Basically it gives you one gear to get it to a service station for repair. I took it to a shop and they told me the code said something about a selinoid fault. More research and I found out the radiators in the pathfinders fail and leak coolant into the transmission. I bought an aftermarket cooler to install, but found a pretty large factory cooler already up front. I decided to roll with it and just do the radiator bypass and flush. When I flushed it I found the strawberry milkshake of death pouring out. I went ahead and finished the flush hoping new oil would loosen everything up and it would work normal again. Well it pretty much worked. My truck has gone into limp mode 4 times since the new fluid. Shutting it off and restarting always clears it and I can drive normal again. Until 2 days ago. I took my truck on a 2 hour drive on a 100 degree day with the a/c on (I had a 3 week old baby and a wife that refuses to be hot). With only about 1/4 mile left on the trip my truck refused to shift out of 1st gear. RPMs just kept climbing above 5k. I let the truck sit a few hours and have not had a repeat of the incident. On the return trip we left at night when it was about 80 degrees and had no issues. My suspicion is that it just got too hot. I rinsed out he cooler and I also pulled the grille off to let more air hit he cooler since it sits right behind the wide v portion of the grille. Do you guys think I need a bigger cooler? Another flush (oil may have a slight burnt smell now)? A complete rebuild? A new truck entirely? I have almost exclusively owned manual transmission vehicles in the past and this truck is making me hate autos even more. I've had tranny trouble in all 4 autos I've owned. Sorry for the long post. Thanks for reading. Any insight is appreciated.


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HiBRiD109
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Postby HiBRiD109 » Mon Jul 17, 2017 11:51 am

Sorry to hear about your issues. I've owned 5 automatic and 1 manual vehicles and I have not had any transmission problems yet (knock on wood). So you may just have a string of bad luck or I need to play the lottery more.

You shouldn't need a larger cooler. I see a few members here who haul large trailers up mountains and not overheat with the stock cooler(keeping it out of O/D).

From what I understand, coolant is heavier than ATF so its sits in the pan. It could (with no real leg to stand on) be that youre fine at the start up but after a while of driving, the coolant mix gets pulled into the transmission valve body from pan and clogging the valve body triggering the TCM to go into limp mode. So when you shut it off and restart the coolant seeps back to the pan and the TCM thinks its all good, but i'm just thinking in theory. Personally, I would try to do a drop the pan and dump then do a flush. Otherwise it would be wise to get it "rebuilt" or serviced. I don't know what all goes into repairing these transmissions when the fluid has been contaminated with coolant. I would hate to not have a vehicle be reliable, especially with an infant. I would find out the costs from a few shops and then weigh out the pros and cons on what to do. You could cough a few crumbs and fix this with a simple flush that may or may not fix the problem, toss a few slices on a rebuilt transmission which should fix it depending on how well the shop did, or pinch a loaf and buy a different vehicle.

EvilTheCat
Posts: 59
Joined: Fri Feb 17, 2017 10:03 pm
Location: Lincoln, ne

Postby EvilTheCat » Sun Jul 30, 2017 6:54 pm

Well I bought a used valve body on eBay from a guy who garaunteed it for 3 years. I put it in today and found reverse to work great. Then 1st worked, then it shifted to second perfectly then third and my truck just slowed way down. Something is seriously messed up. Its worse off than it was. I'll find out tomorrow (monday) if he'll actually honor the garauntee. Maybe this tranny stuff is just over my head. I still don't have any clutch pieces in the pan, so I think the internals are okay. Depending on damage caused by this valve body. Maybe I'll try taking apart the tcm to look for corrosion or damaged connectors. Maybe the solenoid are shot. Maybe an actual transmission shop should look at it. Any advise? I beginning to hate this rig.

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disallow
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Postby disallow » Sun Jul 30, 2017 8:36 pm

Don't get in too deep! Brand new rebuilt available from rockauto for $3400 less $1000 core.

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smj999smj
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Postby smj999smj » Sun Jul 30, 2017 11:45 pm

I'm assuming you installed the used valve body w/ its TCM? If so, did you get it initialized to the ECM? A capable scan tool is needed to program the new TCM to the ECM.

EvilTheCat
Posts: 59
Joined: Fri Feb 17, 2017 10:03 pm
Location: Lincoln, ne

Postby EvilTheCat » Sat Aug 12, 2017 11:09 pm

I did buy a valve body with tcm attached. The guy claimed I would not need to have it flashed or reprogrammed. The install went well. The initial drive however did not. Reverse worked, so I backed it out of the drive way and proceeded down the road. 1st and second gears worked great. 3rd gear not so much. The truck just slowed down as I accelerated. So I brought it back home. Somebody said try to unplug the battery for like 10 minutes and drive it again. This time I could only move forward. Neutral went forward, reverse went forward. Hell, even park tried to go forward. Talking with a transmission expert that I happen to work with, he said the valve body probably had some crossover which made it try to shift into multiple gears at the same time. I called the ebay seller and he said I just need to flash the tcm. I limped it 10 blocks to the nearest transmission shop where they said they could try a flash but it probably needed rebuilt. The flash didn't do a damn thing. I ended up shelling out 3500 to get it rebuilt with a brand new nissan valve body and blank tcm. He showed me the friction plates out of it and they were definitely toast. I am pissed that nissan didn't leave an open recall for this issue. The stupid radiator just cost me a whole lot of money and wasted time. The ebay seller was kind enough to refund my money for the valve body so at least I'm not out 400 there too. Now I'm trying to flush all the slimy oil shit out of my coolant so I can sell this turd. I am through with pathfinders and probably nissan too. I have already put down a deposit and got a loan approved for a subaru outback which I will be picking up Monday. And it does have a manual transmission.

EvilTheCat
Posts: 59
Joined: Fri Feb 17, 2017 10:03 pm
Location: Lincoln, ne

Postby EvilTheCat » Sat Aug 12, 2017 11:20 pm

If you all haven't done it yet, bypass the radiator on your transmission cooler lines. Or get the upgraded radiator that doesn't leak into your transmission and cost you thousand of dollars.

This will most likely be my final post here since my pathfinder will be going up for sale in a couple day. Good luck with yours, mine sucked.


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