5th Gen - AT trans failing - Shop baffled
 

Hi all. Been a while since I last posted. Life gets in the way of hobbies at times.

So the trans on my 2000 GXE Max with 129k miles is starting to flake out on me. :(

Trans occasionally only acted up when towing, and after getting too hot, would refuse to shift into 4th. (I used that as a sign to slow down, lol) I figured I'd need to add an external trans cooler to correct that, as has been discussed here, but I towed so infrequently, I never did.

Now the problem, at only 128k miles, it has started to overheat during regular highway driving if I push it too hard. Here in Texas, it's not uncommon to cruise at ~80-85 mph (usually more) for 20 miles at a time (75 mph speed limit). On a normal hot day 85-95 degrees, this will cause the trans to overheat.

Driving at 70 or below for the same distance, or driving the same speed during the night, has no negative effect.

All other times, the trans shifts fine and acts normal.

It used to trigger the SES light, but doesn't anymore, it just stops working right. When it overheats, I lose all gears except 1st and R (which can be quite exciting in 90 mph traffic). If I stop and idle for 5 minutes, even with the AC blowing, it will start shifting again, and as long as I slow down (accelerate slowly, do the speed limit, up to 65), it doesn't act up again.

We have drained and filled the fluid (it was fairly fresh still), then added an external trans cooler.

I asked my local Nissan dealer but don't trust them, as the first thing they said was time to change the trans. They don't even have an ODB-II scanner to read the codes.

I have not done the solenoids or any other mods.

Any ideas or links to articles or threads here? I read the FAQ's to find some help, but all the links are broken.

Thanks in advance.

Doug

did u say towing..those cars aren t built for towing and it puts strain on the tranny.,,so looks like a replacement may be done...

Of course, what "car" is built for towing. Sorry I misspoke to hide the truth. My wife and I each weigh 300 lbs. Our boys, Cletus and Bubba Jr. also weigh 300 lbs. We come from big boned family. :)
When I try to travel with my family in our big car, its trans overheats. It's a big car and we like it. Is the trans so weak that it can't handle driving a healthy family of four without breaking?

Does anyone have an idea what in the transmission is failing? Could the solenoids just not have the ability to handle heat in the high range of "normal" anymore?

From TX...not sure if joke or truth... :nervous:

I don't know a lot about autos, but did you check to make sure that fluid is being pumped through the cooler lines?

Aren't dealers hilarious? Those lying POS have multiple consult tools that do everything.

Yeah, I was going to suggest the same to make sure the fluid is flowing. You say the fluid looked relatively fresh though, so I can't imagine it wouldn't be, unless it had just been changed before you dumped it. Maybe it would be worthwhile to just go ahead and add an additional trans cooler in conjunction with the radiator. In the process, you'd get to check all the hoses and make sure things are flowing, and the additional cooler couldn't hurt, especially since it's hot and you say it can go on extended higher speed drives. Truth be told though, things are getting old, so it may be time to try to find someone who knows what they're doing (unlike the dealership) to check the transmission out.

Never thought I'd get such a good laugh out of this thread. Haha

Weird with so little miles, I guess age has to do with it too, as mines is at 190k and I can see its starting to give out real slowly but can last as long as I don't beat on it....sucks when you love to beat on it lol. I changed my solenoids recently cause of A code p0744, fixed the problem with A shift delay problem I had but after A week or two the code came back even tho it was shifting better....so maybe my valvebody is next or A new tranny or 5 speed swap or new car lol. What did the ses light say that you triggered? Code?

Well you didn't have to be flippant to someone who asked about the towing. Towing matters greatly for these cars as the auto tranny is weak already and not really built to last. Many people on here have auto tranny problems like yours without towing.

I honestly think you waited too late to install the Trans cooler and now are paying the price. You will likely have to change out the transmission.

Although...did you drop the pan and check the condition such as metal shavings or dust around the magnets? Doing that can be telling, but given your symptoms I can tell you it isn't the solenoids. Either it is the VB or the main transmission.

Try changing the trans filter if you haven't.

Which part? :)



I will check with my mechanic (Acura Master Mechanic), but I would imagine he has checked that basics.



It's really sad that they don't support their older cars. I run into the same problem with my older bikes.


Does anyone have a hookup on a Nissan guru for these older cars in the DFW, TX area? (preferably South Westerly)


Thanks, Doug

If I can't do anything useful, at least I can occasionally bring a smile to someone. :)


Thanks,


Doug

My thought exactly. Having nursed my '99 Supercharged GTP to 230K miles on its stock trans, I was very disappointed to say the least.



Hey, I'm only 50!


I would love to have a 5 speed. I'm thinking of selling this one and buying one just like it with a 5 speed, lol.


Sadly, the dealership wouldn't read the SES code for me without charging $99, then told me they couldn't read it anyway. Then it went away and hasn't come back.


Thanks,


Doug

Sorry boss, just trying to be funny while showing that the concept of moving 1200lbs of payload is not outside the realm of likely possibilities for a larger car such as this. While I may have fudged a bit on our weights, (my wife actually weighing nothing) it is not uncommon for me to drive around with ~950lbs of meat (me and 4 adult passengers) in the passenger compartment. (I did the math, we did weightloss competitions together). Any towing I occasionally did, was by myself, and did not far exceed this weight. Light trailer & 1 motorcycle. (maybe 6 times?)


Crap crap crap crap


OK, great. Thanks for that info.

Doug

I don't believe we have looked into that. Would a clogged filter restrict the coolant flow enough to cause internal overheating? Sounds plausible.


Thanks,


Doug

Understood, but these transmissions are weak...seriously. When I had 30K miles on my 2k way back when I upgraded the VB, installed a transmission cooler, and switched to synthetic ATF. Even with those changes my transmission overheated a few times over the years and I had to change out the solenoids a couple years ago due to slipping.

Point being...these transmissions are weaksauce and not built like other vehicle transmissions.

Luckily...the transmission has held overall and I'm still on the original transmission at 285,000 miles.

Not Maxima's, but I've had cars towed in that gave out when driving, nothing but a clogged trans filter.
Cheap enough to do.

That sounds great. Do you think these steps (including changing the filter) would be beneficial to one that is getting hot, or is there some sort of damage done, that ONLY shows up when the car is being pushed hard?


The fact is, it pulls very hard when cold. No shudders, squeaks, or slips. For that matter, it never "slips". The higher gears just become unavailable until I give it a rest.


It just seems to me, that if something were damaged, it would show up in ALL driving, including bumper to bumper heat, but it doesn't. It's only when the car is being asked to work hard, such as fast driving in the heat of the day, or hauling a mild amount of weight.

Thanks everyone for your comments and interest.

Doug

But these don't have filters. A widely spaced screen isn't a filter.

So fluid flow related to that isn't a problem. The screen is there to catch chunks :laugh:

Thought the screen was a very, very small mesh style screen, no?

Wasn't small on my 2000 auto. If that's clogged up, then his tranny is toast, anyway. I guess he can pull the pan and look.

You may very well be right as I don't remember. I have a ATF "filter/gasket" in the back garage, but as I'm
in Florida right now, that certainly doesn't help.

It is a screen..hardly a filter that would get clogged.

OP's best bet at this point is to pull the pan and do a visual check for shavings and metal dust buildup.

OK, so we can rule out the filter/screen it sounds like.

Looks like I have one of two things that is going on:
1. The heat is normal, and a component is failing and can't take the heat.
2. The heat is not normal, and something is causing it to be excessive

Solenoids have already been said to not be the problem in this thread.

If 1, would a valve body misbehave if it were worn out, and be affected by normal heat?

If 2, could a valve body misbehaving cause excessive heat, and the shifting issue, or is the only cause for excessive heat something internal that is rubbing too hard and creating more heat than it should. (assuming the cooling circuit isn't clogged). (can anything unclog a clogged cooling circuit?)


I really don't think this 15 year old car has enough value in it to justify rebuilding the trans, if it is something internal, but I don't mind doing a valvebody and solenoids if there is a chance that might fix it.

Does anyone have a link to a person or shop that is familiar with these transmissions well enough to answer those questions?


Thanks,

Doug

This is all theory until you drop your pan.

Let us now what you find in your pan. Otherwise your theories will go on and on and on....making this kind of pointless.

What is the temp u r seeing and where is the sensor?

Know have beem stated previously, but nothing blocking the lower part of the radiator and fluid flowing through radiator cooler without any interruption?
See you installed an external cooler-Is it installed correctly to receive the fluid FROM the radiator to the transmission?

Does your od light flash 16 times upon start up by any chance?

It does not.

Thanks,

Doug

We haven't dropped the pan yet, but the fluid drained had no particles in it.

I have spoken with a local trans shop, and they are going to run a diagnosis on it and check the ODB-II code and scan to see the slippage. Their theory is the clutch or whatever is not locking up under load, causing the heat or something to build up (or pressure go down).

It will be good to know what is going on.

Thanks,
Doug

It is a guess. As it only happens when the car is being pushed, it is either a heat or pressure change that is causing the problem. The fact the stopping and idling for 5 minutes returns normal operation makes me think it is cooling off. It could also be pressure returning to normal I suppose, and not be heat related.
I'll know more once the trans shop runs their diagnosis.
Thanks,
Doug

Well, bad news. The transmission shop can find nothing wrong with the car. :( (I know it sounds good...)

No codes, no slippage, or misbehaving. They said it is fine, which it is, up until the point when it fails and the car redlines and slows to 1st gear speed.

So no physical evidence (no metal shavings or granules in the fluid), and no historical evidence (no codes recorded), and no testing evidence (worked fine in all their drive and diagnostic tests).

Yet, if I pull something or drive fast on the highway, it fails after a bit of being asked to work hard, and starts working again after a bit of cool down time (5 minutes) on the side of the road.

What next? Any transmission gurus here? :) (exorcists?)

It may be time to trade her in. I'm sad about that. It is an otherwise perfect car.


https://cimg2.ibsrv.net/gimg/maxima....5e326afc56.jpg

Thanks,
Doug

Or....just don't tow anything or push it really hrs. If you have to tow things consider another vehicle that is setup to tow things....

Do yourself a favor and if you really like the car and would like to keep it try a transgo hd2 shift kit. It has changed my car dramatically. The auto in these cars is not as weak as what people are saying as a matter of fact it's pretty stout. Try the shift kit and see if it makes a difference. How can a auto tranny that puts down 10 second 1/4 mile times with crazy hp be so weak?? Try this option if you want to keep the car. Transgo hd2 and maybe solenoids

Change your revolution speed sensor
https://cimg1.ibsrv.net/gimg/maxima....67aac43983.png

Thank me later, and don't give up on A great car trust me this is ur problem I'm 99% sure.

Thanks man! On your suggestion, I found another thread on this forum discussing this, and looks like you have identified what may the culprit.

https://maxima.org/forums/5th-genera...ed-sensor.html

I'll swap it and let you know.

Doug

Thanks man, I'll look into those too.
Doug

Well, that would be the sane, adult approach. LOL. Thank God I'm not a sane adult yet. Maybe when I hit 60.

Most likely, if I can't fix it, I'll just try to beat it to death to see if I can break it. :laugh:

Then I'll fix it. ;)

Doug

:rotz:

If you have to upgrade the OEM transmission parts to make it "stout" is it really "stout"? Nope...

Besides, this won't fix his symptoms since the issue is not being able to shift into 4th (overdrive). The transgo kit will improve his low end shifting from 1 to 2, and 2 to 3. It has nothing to do with 3 to 4.

The solenoids could be ruled out as well since they typically affect 1 to 2, and 2 to 3 shifting, not 3 to 4 shifting.

As for the revolution sensor...ehhh maybe, but that may just be throwing another useless part at it. What the OP described is exactly the symptoms I had whenever my transmission overheated...basically stuck in 3rd and not shift to 4th. This was with a transmission cooler, a VB mod (transgo kit), transmission cooler, and replaced solenoids. Truth be told I never replaced my revolution sensor, but I haven't had the issue in over 100,000 miles. Then again I don't drive it long distances when it is really hot anymore, and I don't tow anything with it.

It would be silly to throw these parts at it without it likely fixing his issue.

I think I've experienced two separate issues. The overheating when towing and losing 4th, and getting an SES light, and the new issue with losing ALL gears but 1st, and no SES light. Seeing the comments in the other thread, and other comments, I am convinced my car has the same symptoms. So hopefully the same problem, bad RSS. :)

Transgo shift kit doesn't really change parts. I mean not any major ones. The solenoids are just replacing the stock ones with new ones. So no I would say you're changing much if any parts and I stand by my original statement that these trannys are pretty stout. People including me have used them in nitrious turbo'd and supercharged applications. Which most of the time you're adding 100+ hp to the intended hp of the car. I'd say that's pretty stout.

No..it's changing more than that and if you just do a search on here you will see how many people experience AT issues from 5th gen and 5.5 gen. Far more than the people who are running any nitrous, supercharged, or turbo Maximus. Almost everyone (in their right mind) running that stuff all have modified their AT to cope with it.

So no...these transmissions are not stout.