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R34 Gtt - Auto "flaring"

colossus
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colossus Community Regular

colossus

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Posted

Recently had my R34 GTT tip auto serviced (trans fluid flushed and replaced). Before the service the auto was fine, this was just a prevantative maintenance thing as I wasnt sure when the last owner changed the fluid.

Anyway its about a month after the service (this may not have anything to do with the service, just thought i would provide all relevant info - I have also increased boost and added a high flow cat) and now at WOT as you hit redline (this is in full auto mode not tip) instead of just banging in the next gear (like it used to) the gearbox "flares" - what i mean is it feels like the clutch is slipping (if it was a manual) - hard to explain but the revs keep increasing (without the car actually gaining any more speed) holds for a few seconds on the limiter and then changes (costs a lot of time).

Any suggestions?

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colossus Community Regular

colossus

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  • Author
Posted
Look up "Automatic Transmission shift kit" in the group buy section, then ring Mike at MV Automatics and order one.

Yep read all the threads on the MV valve body - it certainly sounds good.

A few things putting me off. Firstly is the problem described above - I want to know if this is something wrong with the box as I dont want to go spending money on a shift kit when that money may be better spent on fixing whatever is wrong with the box (if indeed anything is wrong at all). I.e. it hasnt always done this, its only recently started flaring - so trying to determine if the symptons described above are a result of A) the auto service (maybe they used wrong fluid or did something else wrong), B) more power (boost, exhaust done) or C) Something mechanically wrong with the box.

  • 2 months later...
Dylby77 Explorer

Dylby77

Posted
Posted
Yep read all the threads on the MV valve body - it certainly sounds good.

A few things putting me off. Firstly is the problem described above - I want to know if this is something wrong with the box as I dont want to go spending money on a shift kit when that money may be better spent on fixing whatever is wrong with the box (if indeed anything is wrong at all). I.e. it hasnt always done this, its only recently started flaring - so trying to determine if the symptons described above are a result of A) the auto service (maybe they used wrong fluid or did something else wrong), B) more power (boost, exhaust done) or C) Something mechanically wrong with the box.

Probably the power boost, I put in the the little boost controller, upped the boost then this started happening to mine. I got the stage 2 shift from MV auto's sent it up to QLD got my mechanic to put it in and it was pretty damn good, the bands got tightened and everything at the same time. I can highly recommend the MV shift kit but be prepared to wait because other slack people don't send him back their valve bodies after they get the new one (its an exchange deal)

Thats was 6 months ago, no probs until recently and now it looks like I need to replace the shift solenoids see thread http://www.skylinesaustralia.com/forums/R3...io-t217923.html

just found other guys having same probs, see thread http://www.skylinesaustralia.com/forums/R3...amp;hl=r34+auto

If anyone can tell us how much it should cost to replace the solenoids it would be a great help as my local auto guy has said more than $800!

Cheers

Dylan.

FATAZZ Grand Master

FATAZZ

Posted
Posted

seriously, have you been doing burnouts?

cause thats how i fried my auto box and it had the same symptons as you stated in the early stages

felt like i was holding in a clutch and reving at the same time then later on i completely lost 2nd & 4th gears.

The bloke who rebuilt mine is about 5mins from Hitman.

Dynamic Race Transmission 02 4732 5680 Penrith.

Goodluck.

  • 1 month later...
islade Rising Star

islade

Posted
Posted

Hi guys,

I'm having a similar problem. It seems like my clutch is worn out, except that i have an auto!

In first and second, everything is fine, in 3rd and 4th, if i put the accelator down (even just to creep to highway speed) it feels as though the clutch is slipping, revs go right up and the car doesn't go any faster, and then when you take your foot off, it goes back to the normal revs for that gear/speed.

What did you guys have to get done to fix the problem, and how much did it cost?

Isaac

  • 2 weeks later...
jizza Contributor

jizza

Posted
Posted

I'm experiencing similar problems, particularly when the gearbox is cold is that the same with everyone else? I'm at about 200rwkw now and I'm interested to know how much power the semi-auto can handle? Does the "flaring" damage the gearbox or is it just the electronics interfering to prolong the life of the gearbox?

Cheers,

Justin

DaveB Mentor

DaveB

Posted
Posted

I would also like to know this; I have the same problem with the same gearbox (but mine is in a S2 stagea). Stock power levels & I have had the MV autos shift kit fitted about 3 months ago? I am getting a fault code for shift solenoid A.

Abo Bob Grand Master

Abo Bob

Posted
Posted

What is happening is the bands are slipping. It's the beginning of the end for the box. Mine slipped for ages before I put the shift kit in but it was too late, it blew completely shortly after the kit was fitted so I had to get a full rebuild.

All I can suggest is as soon as this starts happening, stop driving the car in the way that makes it do it. Every slip you have is causing damage. For me it was first gear slipping when cold but there are other times it slips for other people as evidenced by this thread. If you get it early enough one would hope that the shift kit and a tightening of the bands will fix it. You could try an ATF with no friction modifiers but this stuff costs more than a shift kit!

  • 4 weeks later...
DaveB Mentor

DaveB

Posted
Posted

Sorry don't know about Melbourne... thought I might report back on my problems. I took the car to MV autos; they ran some diagnostics and found that shift solenoid A was failing at operating temperature, possibly causing a whole lot of other hiccups in the system (like the slipping in reverse). Also a pressure regulator was suspect. All of this was replaced on the same 'rack'; apparently the solenoid rack replaces most of the internal hydraulic control stuff. Took a day to get the part in and I picked it up the day after; running better than ever now for nearly 5,000K's :) However it brought the total cost of my 1,000K service to over $2,000.... :)

Abo Bob Grand Master

Abo Bob

Posted
Posted
is mv autos the only place that does the shift kit for the r34 auto..... anywhere in melb got the know how???

I tried Keas in Sydney and a place I can't remember the name of in Melbourne who I was told knew their stuff. I also tried MV in Adelaide and after speaking to Mike the choice was clear.

You can get the shift kit from Mike and then get Knox Automatics to fit it for you though.

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