Wiking

So I bought a spare Maxima to support the lifetime love. Got it "cheap" b/c she had decided never to go back wards.

Missing gears: no R, no 2nd, no OD. (1st gear works fine, then when manually changing to 2nd, engine breaking disappears and stays in 1st.) D works ok using those 1&3 gears and going strong.

Question to folks who have experience in servicing A/T mech/hydraulics. Where do these symptoms meet? My guess: theres one only one spot which doesn't click...

What its NOT: No its not electronics or valves, they have been already on kitchen table. When computer is disconnected, still no R, not even a hint (well, maybe 20rpm drop). Everything inside is clean like new (just opened the valve top pan, checked valves). No extra noises. Oil has been changed. 2nd/R brake band was adjusted, as it is visble from top - seems ok.

LvR

Well blow me over - where have you been all the time?

Greeny

iTrader: (43)

Hey wiking!!

Good to see ya posting again..

The trans is defective somewhere,maybe a professional could spot the problems easy?

maxitech

iTrader: (7)

Wow, long time no see! I'm not quite sure how to answer your question, but I just wanted to say welcome back!

sonicii

The one band in the RE4F02A transmission is used in 2nd, 4th and reverse, the band is disengaged for 1st and 3rd. So I am guessing either the band servos or the band itself.

internetautomar

iTrader: (30)

or the housing for the clutches. I used to sell alot of housings and sun gears (other transmissions)

Walt- was there any metal in the pan?

Wiking

Yes my conclusion was also that as all points there. But the band seems ok. The band can be partly seen from top as the valve assy is taken out. Seems like new... I adjusted it, [close/unscrew 5 1/4 turns] and now its about half turn tighter. Not much worn I guess? Seller says A/T has 80kmiles.
I did not open all the valves, just checked the assy that valves move freely and visibly all is clean.

Questions:
- Can the servo be tested, how?
- The servo can be checked/opened w/o taking tranny out, can it? How? The manual is not very helpful here, visibility limited...


Box is absolutely clean inside, no metal chips nothing, oil was about ok...
internetautomar - "lost sun gears" - means lots metal chippings?

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LvR Well blow me over - where have you been all the time?
... hmm. Been lost in the Taiga? Heard the [maxima]nature call and now found my way back into civilized world.

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Pics as pan opened, valve assy out; servo bottom left; band at left:

internetautomar

iTrader: (30)

no metal shavings is a good thing.
did you actually remove the band?
in the picture you can only see the back side not the friction side which is what matters.

Wiking

Little bit of the band can be seen from top [not in this pic]. If band was blown to pieces, tightening would take much more that those 5 1/4 turns the manual cites ... so it seems ok. My guess is the servo, its ctrl or sun gears u mentioned.

This is where I got. Closed and pushed her to the backyard...

Greeny

iTrader: (43)

Pics of new car walt?

Wiking

She's gray old ugly and rotten; not mylove. But. Electric seats... Besides, you've now seen her brains, what more can one ask for?

I will sell her if u can find the easyfix to get her R-rated...

Greeny

iTrader: (43)

Ahh.. ic a rust bucket.

I wish i could help, but a transmission guy i am not..

internetautomar

iTrader: (30)

the band doesn't blow to pieces, like a clutch it glazes over and doesn't grab.

Wiking

Like a clutch: once it starts, its gone? ...and over tightening wont help I guess? Hmm.

The seller said losing R was sudden surprise, not gradual. This is why I suspected servo (ripped o-ring?).

When [if ever] band is taken out, glassing is visible I guess. Drop the tranny, uh. Wasnt my plan...

internetautomar

iTrader: (30)

toss in some "transmission fix in a bottle" if it's a car that you aren't keeping. that may help it.

Greeny

iTrader: (43)

My wifes auto vg was slipping pretty bad in 2nd gear about a month ago, i done several fluid changes on it over a weeks time,with driving in between..It does not slip in any gear now..

though your trans seems to be in much worse shape then mine,it might bring back the gears for a while.

Deridex

Dude, I've had the exact same thing happen. If you look in the service manual, it says that trasmission has what they call "safe mode", where the only gear that works is the 2nd. I just replaced the whole thing.

CapedCadaver

iTrader: (8)

actually it's supposed to be 3rd. that's because both solenoids are off in 3rd (1st AB, 2nd B, 3rd -, 4th A)

goon9

iTrader: (13)

Wiking is back! Long time buddy

internetautomar

iTrader: (30)

alot of trans lock into 2nd gear as a fail safe.
it's able to get the car moving and maintain a decent speed. 1st and 3rd can't do both.

CapedCadaver

iTrader: (8)

yeah i know the 93 galant will stay in 2nd. but on the VG auto, it just so happens to be 3rd, since i have switches to cut power to the shift solenoids, and if i mess with any of them, the car stays locked in 3rd no matter what. i have to shut the ignition off and back on (rolling) with the solenoids enabled to reset the TCU so i can use other gears again. I've made the car move in 3rd after stopping with the switches off, and it goes.... kindasorta but takes a hot minute to get to 15 but after it reaches about 20mph it goes just fine.

Matt93SE

iTrader: (44)

Hey Wiking! ready for another arguement where nobody understands what you're trying to say?

If you were on this side of the planet, I'd say go get a junkyard tranny and call it a day. but I'm sure replacements aren't as easy or cheap over there.

I'm not entirely familiar with autos, but I'll try to help w/ 3rd grade troubleshooting...

have you checked the solenoids themselves? is there a way to check line pressure coming out of them?

Is there any other way the clutch band wouldn't engage?
can you manually fire off a solenoid and engage the band? i.e. here, some tranny shops have a tester they can plug into the nissan harness and control the thing manually.

do you have a spare tranny computer you can try?

BenStoked

iTrader: (7)

matt, i didnt think you could do 3rd grade anything on our cars. (matt has a weakness in autos!)
j/k matt, why have an auto when you can have a 5 speed! amirite?

Matt93SE

iTrader: (44)

I always prefer to row my own, but autos have their advantages.. like when my wife is driving..

VEvolution

nice to see u back wiking..

yea autos do have their uses espeically in over populated cities

Deridex

That's inretesting. Back when I had the problem (and I've had it for about 6months), the car still had reasonable acceleration. I mean, it didn't accelerate fast, but contrary to what I expected it did better than I thought going up steep hills and I even got on a highway once reaching 60 mph before it started makng clanking noise. To explain why I did the latter, I just thought to myself "my transmission is screwed, so how much worse can it really get?" Maybe that wasn't the safe mode on mine then.

BenStoked

iTrader: (7)

yeah, i could see traffic being a problem. on the rare occasion we have traffic, its BAD! i have to drive by releasing the clutch to move 5-10 ft at a time, stop,repeat. after 15 minutes, my knee is killing me. luckily, okc, ok isnt bad (usually)
anywho, my brother's altima is having a similar issue. if you find an easy solution, lemme know before he has it rebuilt/replaced...(similar(ish) tranny, maybe able to apply the same principles to fix it)

sonicii

The servo is activated by fluid pressure, when rebuilding a transmission, most mechanics will check the servos with compressed air to ensure they operate, I am not sure if this can be done on a transmission in the vehicle and with fluid in it, but I suspect it can. Also, I don't think the band servo pressure is available on an external pressure test port like the line pressure, clutch servos and lockup pressure. A transmission shop will probably have a control unit they can use to manually control the transmission while driving the car, but they will only be able to control the shift solenoids, line pressure and lockup, they won't be able to control the band servo directly. To access the band servo, you will need to remove the transmission and dismantle it.

Wiking

BUT. The servo 'pckg' opens from outside, doesnt it? If so, the piston can be taken out w/o dropping tranny. [Pics please, anybody] ...

NOT in Safe Mode: thats electronically initiated ... Pls do Read my opening post again.

internetautomar

iTrader: (30)

walt- did you check the color / smell of the transmission fluid in there now?
a burnt smell/color will indicate a definitely toasted trans.

This is a case where serious labor is needed to diagnosis it with 100% accuracy

BenStoked

iTrader: (7)

the fluid in the pics above looks burnt. shouldnt tranny fluid be pink or something(I just woke up, not thinking yet)? thats is most definitely brown.

internetautomar

iTrader: (30)

it does look old, that is for sure.
Burnt I can't tell from the pic

sonicii

You may be able to take the casing off the transmission while it is still in the car, but I imagine it would be fairly tight. Can't say I have heard of anyone doing that.

I'm not suggesting the problem is safe mode or electronic (from the symptoms, I would almost certainlly say it isn't), but some suggested a mechanic could control the band servo manually with a 'plug-in' unit, and I was just stating that they cannot control the band servo directly, only the shift solenoids, etc.

Its too hard to tell from the picture if the fluid is burnt, the smell is the easiest way to tell.

Keep in mind all of the opinions here are only speculation based on the symptoms. The only wat to tell for sure exactly what is wrong is for an experienced trans. mechanic to dismantle the transmission and diagnose the problem. And that is most likely what any trans. mechanic will want to do if you take it to them, you will be unlikely to find one who will narrow down their diagnosis based on what you or anyone here has said.

Maxpwer

iTrader: (7)

Wiking! I really glad to see you are back. Im afraid I dont know much about auto transmissions, but I had to say hello and I cant wait to see some more threads by you!

Wiking

Hi thks Maxpwer plus yall with positively mindset. Its been long lonely hard walk in the freezin Taiga snow... but now here I am happy (am I?) with my spare maxima problem. (Alas, my crown jewel 2nd now slips a little bit, this keeps me melancholic: under 7s to 60mph not possible anymore).

Yes, so it is. Things presented online always lack the stink... Me not even wannabe tranny mech... becoming one - nearest CCCP? I'll make a try to access this sevobit after AlGore comes and shovels out all the snow...
What should I then see in my hand? ...pics pls! (Btw. The 'safe-mode' bit for was just comment on other posts...)

Diag-nose: "The oil didnt stink!" I guess that could be a physical problem between my eyes? Or maybe my diag-nose was hijacked by the rotten tobacco/bourbon stink filling the garage
The statement seems also unreliable Because the jeans and jacket used with splashed A/T oil (week later) made a headache anyone in the house. Hmm. Here we are again: "The only wat to tell for sure exactly... " is to go and suck it. Even that needs faith.

CapedCadaver

iTrader: (8)

hokay, finally found real confirmation of which gear Failsafe induces. it's found in the FSM on AT-25 for the VG and AT-96 on the VE. Says 3rd. I know we know that Wiking is not having that problem but i just wanted to clear up any possible misunderstanding or he-said-she-said so that everyone knows for sure what it is. No disrespect to anyone.

Wiking

After/During full emergency brake [ABS engaged], a loose pckg in the cabin hit my gear lever and pushed it to N. This chain of events caused 3rd gear to fix on. Awful pwrless feeling after surviving a hit from self propelled blondie 'bomb'... There I thought the tranny was at last becoming domestic = Finnish'ed. Limped my max to a parking space, went for my business = ign off... As of return, after startup, all was ok. Later studied the FSM [thks interneta...:] and was convinced that was is a failsafe -experience.

As said, the tranny hydraulics will 'function' up to a degree if computer is DISconnected - especially forward and R will 'move' the vehicle. (I did not tst drive on the road, just stationary vehicle). With my spare rotten max, no R, with or without TCU. So I'll concentrate on the clutch servo, then drop tranny as necessary ... if June is given to me.

internetautomar

iTrader: (30)

you are welcome.

Wiking

Update:

1st: Snow has melted, repair can be done w/o skis

2nd: The servo can be opened tranny on. Took one hour ... now stinking on the kitchen table. The inner snap ring needs workin eyes closed, see the servo structure at FSM AT-216.

1+2= Only 'fault' I can see is the outmost O-ring which resembles german würst (sausage). But cant see how it could cause anything but a leak... Tranny is dirty, but not oily.

The other rubber O-rings seem adequate in their job. Not new... (they resemble piston rings in their form.).

There is the upgrade kit. Is it for these, has anybody bought /installed the 50$ kit? ... Service pack for RE4F04A auto tranny: www.txchange.com