94 6 spd grinds into 3rd gear - please help
Thread Starter
Burning Brakes
Joined: Jul 2002
Posts: 1,027
Likes: 245
From: Boise ID
94 6 spd grinds into 3rd gear - please help
My 6 spd grinds into 3rd gear almost every time. If I shift real slow and let the RPMs fall between 2nd and 3rd then it does not grind but if you are going through the gears with any sort of purpose it grinds.
Does anyone know of a cure or even the cause for this?
Does anyone know of a cure or even the cause for this?
Thread Starter
Burning Brakes
Joined: Jul 2002
Posts: 1,027
Likes: 245
From: Boise ID
Re: 94 6 spd grinds into 3rd gear - please help (jfb)
This sounds like a bad thing.... I don't suppose the home mechanic can do the rebuild?? The tranny sat since 1999, is there a chance that a fluid change could resolve some of the problems I am having?
Safety Car
Joined: May 2002
Posts: 4,010
Likes: 26
From: Somewhere nowhere
Re: 94 6 spd grinds into 3rd gear - please help
the fluid change will definately help. it won't solve the problem, but will make shifting easier. for a while at least... until you feel like yanking the tranny out.
Race Director
Joined: Nov 1999
Posts: 14,577
Likes: 0
From: Michigan in the summer, Florida the rest of the time
St. Jude Donor '08-'09-'11
Re: 94 6 spd grinds into 3rd gear - please help (AEmedic)
You need to describe the symptoms and history to THE expert on the ZF's - Bill Boudreau. Reach him at billb@ZFDOC.COM or stop by his site http://www.zfdoc.com for lots of FAQs.
If your ZF does need repair, Bill's just the guru you'll need.
BTW, a quote from his site:
[Modified by GS Ragtop, 8:25 AM 11/2/2003]
If your ZF does need repair, Bill's just the guru you'll need.
BTW, a quote from his site:
To date we have rebuilt 152 ZF S6-40 transmissions. I would say that 94% of those units were primarily damaged while operating with some type of degraded hydraulic clutch condition.
[Modified by GS Ragtop, 8:25 AM 11/2/2003]
Drifting
Joined: Aug 2003
Posts: 1,565
Likes: 2
From: somewhere between heaven and hell WI
Re: 94 6 spd grinds into 3rd gear - please help (AEmedic)
One thing you may want to try is a fluid change.
I have a 84 with a Richmond 6 speed and I was getting a grind EVERY time I shifted into 2nd gear. My friend sugested use GM SYNCROMSH Fluid. I tried it and it has not grinded (grammer?) since.
The fluid is about $9-10 bucks a quart, but it saved me from rebuilding my trans. You can get the fluid at a dealership.
Good Luck and let us know what you do.
:steering:
I have a 84 with a Richmond 6 speed and I was getting a grind EVERY time I shifted into 2nd gear. My friend sugested use GM SYNCROMSH Fluid. I tried it and it has not grinded (grammer?) since.
The fluid is about $9-10 bucks a quart, but it saved me from rebuilding my trans. You can get the fluid at a dealership.
Good Luck and let us know what you do.
:steering:
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Thread Starter
Burning Brakes
Joined: Jul 2002
Posts: 1,027
Likes: 245
From: Boise ID
Re: 94 6 spd grinds into 3rd gear - please help (ffvetteman)
This is what I was hoping, I am going to change the fluid and see what happens.
I am fairly certain that the engine and tranny sat out at the salvage yard rather than in a car for awhile prior to it ending up in my vette.
I have been putting this car back together for over a year and just got it into 3rd gear for the first time yesterday.
Can you lose fluid taking it out or putting it in the car? If so it could be low on fluid and I will find that out too
I am fairly certain that the engine and tranny sat out at the salvage yard rather than in a car for awhile prior to it ending up in my vette.
I have been putting this car back together for over a year and just got it into 3rd gear for the first time yesterday.
Can you lose fluid taking it out or putting it in the car? If so it could be low on fluid and I will find that out too
Melting Slicks
Joined: Apr 2000
Posts: 3,198
Likes: 2
From: Northern CA
Re: 94 6 spd grinds into 3rd gear - please help (AEmedic)
I seem to remember ZFDoc mentioning that when the clutch hydrualics fail, the 3rd gear synchro is often the first one to go. In your case the damage is already done, but I'd make sure you check the clutch hydraulics are up to par so it doesn't happen again after a rebuild. GOod luck :cheers:
Racer
Joined: Jul 2002
Posts: 401
Likes: 1
From: Aptos CA
Re: 94 6 spd grinds into 3rd gear - please help (AEmedic)
My 3rd synchro has always been bad. I bought it in 92 with 32K on it. I figured either the previous owner was a jerk, or potential buyers had missed some torgue shifts. I now have 89k on that synchro and it's the same has the day I bought it.
Team Owner
Joined: Aug 2000
Posts: 40,156
Likes: 45
From: San Pedro CA
Re: 94 6 spd grinds into 3rd gear - please help (Skippy Stone)
when you replace the fluid, use the BMW factory fill, 10w-60 Castrol TWS.
This transmission is NOT a DIY project... these are complex transmissions...
This transmission is NOT a DIY project... these are complex transmissions...
Le Mans Master
Joined: Apr 2002
Posts: 5,727
Likes: 46
From: Waukesha WI
St. Jude Donor '15
Add another vote for the fluid change.
My 90 with 125k on the clock used to really have a hard time with third gear and sometimes 4th. I changed fluid to GM and it improved a bit but not enough to make me feel better.
I switched to the BMW stuff and WOW. There is still a little stiffness in the shifting but it is almost not noticable. I am impressed that just a simple fluid change made a world of difference but I am a believer.
My 90 with 125k on the clock used to really have a hard time with third gear and sometimes 4th. I changed fluid to GM and it improved a bit but not enough to make me feel better.
I switched to the BMW stuff and WOW. There is still a little stiffness in the shifting but it is almost not noticable. I am impressed that just a simple fluid change made a world of difference but I am a believer.
Thread Starter
Burning Brakes
Joined: Jul 2002
Posts: 1,027
Likes: 245
From: Boise ID
Re: 94 6 spd grinds into 3rd gear - please help (JasonL)
Although I don't think the damage is due to the present setup I can say that my clutch hydraulics had to flushed a good deal to get it to work, like I said it sat for along time, but once I bled it well it did not have a problem, at least all the gears except 3rd are fine...
Thread Starter
Burning Brakes
Joined: Jul 2002
Posts: 1,027
Likes: 245
From: Boise ID
Re: (Professor)
Thanks Professor! I like all the good news I can get!
Does anyone know anything about Redline MTL I keep reading that ZF Doc recomends it as well and it is totally synthetic so maybe it won't break down as much as the Castrol
Any Opinions?
Chris
Does anyone know anything about Redline MTL I keep reading that ZF Doc recomends it as well and it is totally synthetic so maybe it won't break down as much as the Castrol
Any Opinions?
Chris
Melting Slicks
Joined: Aug 2000
Posts: 2,925
Likes: 3
From: Dover NH
Re: (AEmedic)
Thanks Professor! I like all the good news I can get!
Does anyone know anything about Redline MTL I keep reading that ZF Doc recomends it as well and it is totally synthetic so maybe it won't break down as much as the Castrol
Any Opinions?
Chris
Does anyone know anything about Redline MTL I keep reading that ZF Doc recomends it as well and it is totally synthetic so maybe it won't break down as much as the Castrol
Any Opinions?
Chris
I thought the ZFdoc recommends the GM, or the fully synthetic castrol?
I didn't think Redline was mentioned on his web site?
Thread Starter
Burning Brakes
Joined: Jul 2002
Posts: 1,027
Likes: 245
From: Boise ID
Re: (Bans25)
I read a number of archived posts that mention him endorsing the Redline MTL as well as the GM and Castrol. I did not get that info off of his site however.
[Modified by AEmedic, 5:46 PM 11/2/2003]
[Modified by AEmedic, 5:46 PM 11/2/2003]
Le Mans Master
Joined: Apr 2002
Posts: 5,727
Likes: 46
From: Waukesha WI
St. Jude Donor '15
To date, the Castrol and the GM fluid are the only ones around endorsed by the manufacturer. There are a few forum members using the Redline with no problems. ZF also recommends Auto tranny fluid (that meets their specs) but I don't think anyone is using it.
Melting Slicks
Joined: Apr 2003
Posts: 2,150
Likes: 6
From: NS
Re: (AEmedic)
Thanks Professor! I like all the good news I can get!
Does anyone know anything about Redline MTL I keep reading that ZF Doc recomends it as well and it is totally synthetic so maybe it won't break down as much as the Castrol
Any Opinions?
Chris
Does anyone know anything about Redline MTL I keep reading that ZF Doc recomends it as well and it is totally synthetic so maybe it won't break down as much as the Castrol
Any Opinions?
Chris
I recently switched to the Castrol stuff and noticed no difference in my tranny. Mine's working fine right now (no grinding), just a weird "two-step" notchy feeling in 3rd (and sometimes other gears) that's been there for some time now. Anyone else have this?
:cheers:
[Modified by Atok, 5:50 PM 11/3/2003]