Transmission Questions VG30

[Tim H]

Hi List,

When I put my wagon together, I rebuilt the 5 speed (FS5W71C) with new
bearing and synchros, and the transmission works OK, doesn't make an
noise, shifts fine in all gears, except 2nd. In normal shifting into
2nd, there is no problem, but if I'm getting on it, the 1st to 2nd
shift can be a problem in that I must shift slower than I'd like to be
sure that I get 2nd. It will shift but it is not smooth.

As I move through things I don't like about the build, the
transmission is next on my list. I would like to get something that
shifts smoothly that I'm not afraid to hammer. So, my question to you
transmission experts are:

Is this too much to expect out of the FS5W71C? (This was out of a Z31
(84 300ZX)).

Should I get another transmission or get this rebuilt?

If I go the re-building route, what needs to be done to get it right?

Is there anyone you might suggest that can help?

And to Dave Lum, I've seen that it is possible to mount the 5 speed
from the Z32 (RS5R30A) on the VG30, but will it fit in the 510
tunnel? This has been documented for the Z31 on the 31performance
forum, but not for a 510 with a VG30.

Thanks for any advice.

Thanks for any advice?

[Desert Datsuns]

It's usually best to rebuild the one you have, that way you know it's in
good shape. If you buy another used one, you have no idea if it will
last a week, or 5 years.

It just sounds to me like your synchros are going. On mine you have to
shift slow when going from 3rd to second, mine are on their way out too.
Ryan Newman
Phoenix, AZ
71 510
81 280ZXT
06 Frontier

[David Carroll]

Tim & list,
You should be able to hammer 2nd as hard as you want if the synchros are in
good shape and you've got the right fluid in the transmission. Mine can be
power shifted all day long as hard as I want to beat on it and it just
snicks into gear effortlessly every time. Likewise I can downshift to 2nd
with a half-clutch and throttle blip that puts the motor to 7500rpm when the
clutch re-connects. The FS5W71C is my favorite shifting Nissan manual
transmission and I have driven them all, including many years driving a
servo-synchro Nismo race trans every day.

I have run into trouble in the past with synthetic gear oil being "too
slick" for synchros to work properly. If you have synthetic in it you might
try plain 85W90 and see what happens. If you're running that now put in half
a quart of Hilton's Hyper Lube and it will probably smooth out a whole bunch
until you can do the synchros.

If you rebuild any transmission, especially a Nissan one, here's a trick my
trans builder/rebuilder taught me that typically doubles their life: Get a
sealed bearing for the countershaft where it passes through the center
plate. You MUST remove the forward seal or the bearing will burn up! By
leaving the rear seal in place oil (with fine ground metal in it) no longer
constantly washes back-and-forth through the bearing. You leave the seal in
the rear of the bearing to insure the bearing is submerged in oil when
accelerating. Also so that chips off the reverse gears cannot wash through
the bearing on their way to the magnetic drain plug. Failure of that bearing
is the #1 cause of transmission failures. There are oil holes in the center
plate so oil can still flow freely to everywhere it needs to go. Adding a
magnet in the bottom of the tail housing would help too as wear of the
reverse gears produces most of the fine ground steel found on drain plug
magnets.

Thanks!
David Carroll
Evil Genius
Experimental Engineering
www.vg30.com
.

Hi List,

Thanks for any advice.

Thanks for any advice?

--
NOTICE!!!!

All emails will be sent to the author of this message. If you want to send
this message to the group simply add this address to the "To" field in your
email client blueb...@googlegroups.com .

[Tim]

Dave,

I'm Redline Synthetic now. I'll swap it out for some plain 85W90 and
see what happens. Thanks for the input. Your experience with the
FSW71C really makes a huge difference to me. Now I know it can work
very well.

Tim

On 2/6/2012 5:38 PM, David Carroll wrote:
> Tim& list,

[Harry Jones]

About your question on the z32 trans in a 510 the answer is yes and no. It will fit but it requires cutting the floor to clear the starter. The better solution is the z31 or patherfinder/frontier/xterra transmission. All are(FS5R30) and are the same basic transmission with a forward facing starter like the FS5R71C. Just keep in mind they are all physically bigger and stronger transmission than your current one.

Harry

Sent from my iPad

[Bruce Palmer]

Tim,
You should be good to go because your synchros are still fairly young..... Report back how the switch works.

Bruce Palmer
Sa...@Ztherapy.com

 

> Date: Mon, 6 Feb 2012 19:06:20 -0600
> From: 5...@specs-houston.com
> To: blueb...@googlegroups.com
> Subject: Re: [Bluebird510] Transmission Questions VG30

[David Carroll]

Tim & list,
I look forward to hearing if the fluid change solves or reduces the problem.
I would drive it a bit, say 100 miles, before making a judgment about how it
shifts. It takes some use to get every remaining bit of the old lube mixed
evenly into the new stuff. If it shifts better after 100 miles I'll bet it
gets even smoother after 500.

They really are a great transmission and one of Nissan's toughest to hurt
with driver abuse. As with most transmissions the limiting factor in their
strength is the bearings used. My 'good one' has maximum capacity bearings
throughout. Your typical transmission bearing has about 7 ball bearings in
it and they are spaced apart with metal or plastic spreaders to keep them
evenly spaced. What happens is when you apply a massive load to the gears
the shafts try to spread apart. If you load the bearings hard enough the
balls will spread apart due to flex in, or failure of, the spreaders. As the
gear lash (spacing between shafts) increases the leverage against the
bearings increases even more. This means they spread even further
multiplying the problem. Maximum capacity bearings typically have either no
spreaders so the balls rub on each other or they have very thin, hard
plastic spacers that are more like washers. The ball count is much higher
as is the load carrying capacity. Since the shafts cannot spread apart under
load with these bearings the transmission is effectively much stronger.

If you take an FS5W71C apart and put it's internals next to a Super T-10s
the Nissan transmission's parts are clearly larger and the quality of
materials is undoubtedly better. Super T-10s with good bearings laugh at
600hp small blocks in late model stock cars. My transmission guy says with
max capacity bearings the weakest link in an FS5W71C is the output shaft
itself. His best guess is it would take 500 lb.-ft. of torque *hooked up* in
first gear to twist that shaft in two. I know all the drift idiots are
swapping FS5R30A (Z32) transmissions onto their SR20DETs because they are
cheaper and stronger than SR transmissions. Out of the box (or rather
wrecking yard) there is no doubt that's a strong transmission. When you
start with a gearbox with 150k miles on it and then do full throttle clutch
kicks constantly I guess the extra 'beef' of the 30A trans is the cheapest
solution. It's also ~40 pounds? heavier, adds a bunch of parasitic drag, and
shifts like a bucket of mush.

I have yet to personally see a 510 capable of hooking up enough power to
break an FS5W71C, even with stock bearings in good condition. Bolt in a 200k
mile POS from a wrecking yard and yeah, you might break it in a 510 if you
abuse it hard enough. Short of clutch kicks I have beaten the piss out of
these transmissions every way possible and have never broken one, either
stock or with good bearings. I guess I've logged about 250k miles total so
far in my two VG510s.

Thanks!
David Carroll
Evil Genius
Experimental Engineering
www.vg30.com
.

-----Original Message-----
From: blueb...@googlegroups.com
[mailto:blueb...@googlegroups.com]On Behalf Of Tim

Sent: Monday, February 06, 2012 5:06 PM
To: blueb...@googlegroups.com
Subject: Re: [Bluebird510] Transmission Questions VG30

[Jordan B]

For what it's worth, long ago I changed out my original Z31 transmission in my VG 510. It was not because of any mechanical failure, but because of excessive bearing noise whenever the clutch was engaged. 

That trans had over 150K when I pulled it from the most beat up 300zx you have ever seen. I may have added another 10K of spirited driving and a few Shasta trips. 

When I drained the oil, it honestly looked like silvery grey metallic goo. Again, the transmission preformed and shifted just fine.

Jordan B

[David Patten]

Just a quick note on the type of fluid.

 

If the synchro rings are brass/bronze you should use a GL4 gear lube. The later transmissions usually call for GL5 fluid, which can be corrosive to yellow metals (ie brass synchro rings).

 

Links:

http://www.mobiloil.com/usa-english/motoroil/car_care/askmobil/GL-5_and_GL-4_Gear_Oil.aspx

And

http://www.mobiloil.com/USA-English/MotorOil/Car_Care/AskMobil/GL-4_Gear_Lube.aspx

 

BG Synchro Shift. While I have never used the product it comes highly reccomended by a fellow 510 racer who has. He had rouble with high speed shifting in his racecar and switched to BG Synchro Shift gear lube. He claimed it took all the "crunch" out of his shifts. It might be worth looking into.

 

Dave Patten

Dunbarton, NH

[Tim H]

Well, I can see a couple of things that need to be tried. First, I
will change the fluid to a GL4 standard since mine does have the brass/
bronze synchros. Next, It really looks like I will need to go back
into the transmission to replace the synchros. When I re-built it I
purchased aftermarket synchro rings. Since then I have seen a couple
of references about using the Nissan synchro rings. My mistake trying
to save some $ when re-building the car, but the little things really
add up fast! Based on all the comments, it doesn't seem to make any
sense to change the transmission type from the FS5W71C.

Thanks,

Tim H

On Feb 7, 9:08 am, David Patten <dwpat...@gsinet.net> wrote:
> Just a quick note on the type of fluid.
>
> If the synchro rings are brass/bronze you should use a GL4 gear lube. The
> later transmissions usually call for GL5 fluid, which can be corrosive to
> yellow metals (ie brass synchro rings).
>

> Links:http://www.mobiloil.com/usa-english/motoroil/car_care/askmobil/GL-5_a...
> Andhttp://www.mobiloil.com/USA-English/MotorOil/Car_Care/AskMobil/GL-4_G...

>
> BG Synchro Shift. While I have never used the product it comes highly
> reccomended by a fellow 510 racer who has. He had rouble with high speed
> shifting in his racecar and switched to BG Synchro Shift gear lube. He
> claimed it took all the "crunch" out of his shifts. It might be worth
> looking into.
>
> Dave Patten
> Dunbarton, NH
>
>
>
>
>
>
>
> On Tue, Feb 7, 2012 at 12:50 AM, Jordan B <vg30....@gmail.com> wrote:
> > For what it's worth, long ago I changed out my original Z31 transmission
> > in my VG 510. It was not because of any mechanical failure, but because of
> > excessive bearing noise whenever the clutch was engaged.
>
> > That trans had over 150K when I pulled it from the most beat up 300zx you
> > have ever seen. I may have added another 10K of spirited driving and a few
> > Shasta trips.
>
> > When I drained the oil, it honestly looked like silvery grey metallic goo.
> > Again, the transmission preformed and shifted just fine.
>
> > Jordan B
>

[Chris Saulnier]

To follow up on Dave P's comments, GL4 rated fluid is virtually impossible to find at your local auto parts store. Read the details on the bottles, most of them say they are compatible with GL5 & 4. If they are compatible with 5 they have the corrosives that will cause the brass synchro problems. I used Redline MTL which is compatible with the brass rings in my FS5W71B without any issues.

I'd do the fluid change and follow Dave C's advice to run it for at least 100 miles before going to the hassle of a synchro change. Agreed that the Nissan synchros are the best albeit expensive.

Chris of Maine "been there beat on that"

'71 Datsun 510 Wagon - project (V8)
'90 Volvo 745 Wagon - beater
'90 Suburban 2500 2WD - beast
 MOG#7

[br...@windstream.net]

Have you tried using straight automatic transmission fluid ( DEX3 ) at all?
That's what I use in my older Nissan transmission, and it works well for me.

Keith

[David Bliese]

I have used Redline and BG both in my Mitsubishi transmissions that call for GL4 and both have worked well.