Automotive Forums .com - the leading automotive community online! Automotive Forums .com - the leading automotive community online!
Automotive Forums .com - the leading automotive community online! 
-
Latest | 0 Rplys
Go Back   Automotive Forums .com Car Chat > Geo > Metro
Reply Show Printable Version Show Printable Version | Email this Page Email this Page | Subscription Subscribe to this Thread
 
Thread Tools Search this Thread
Old 12-04-2005, 11:16 PM   #1
DOCTORBILL
Geo Metro Lover
 
DOCTORBILL's Avatar
 
Join Date: May 2005
Location: Eastern Washington State, Washington
Posts: 1,616
Thanks: 0
Thanked 0 Times in 0 Posts
Which is Best Manual Transmission Fluid ?

Reading around about Geo Metro manual Transmission fluid, I get
the feeling that this is a controversial topic.

It looks like it is a toss-up between GM Sychromesh and Redline MT-90.

Any fervent opinions from the early 90's Geo Metro owners ?

Mine is a '93 with 3 cyl 5 speed manual.

It shifts nicely, downshifts nicely and I am wondering if I should
change the fluid as I bought it used and GOD ONLY KNOWS if or
when the fluid was changed.

Maybe 'If it ain't broke, don't fix it' applies here since some folks
seem to aquire transmission problems after changing their fluid....

DoctorBill
__________________

DOCTORBILL is offline   Reply With Quote
Old 12-05-2005, 04:20 PM   #2
t-max
AF Newbie
 
Join Date: Nov 2005
Location: detroit, Michigan
Posts: 6
Thanks: 0
Thanked 0 Times in 0 Posts
Re: Which is Best Manual Transmission Fluid ?

I'd change the fluid. As for what brand, well, I will admit that I use a generic brand from Canadian Tire. Perhaps someone will chime in with the benefits of a particular brand.

cheers,

Quote:
Originally Posted by DOCTORBILL
It shifts nicely, downshifts nicely and I am wondering if I should
change the fluid as I bought it used and GOD ONLY KNOWS if or
when the fluid was changed.

Maybe 'If it ain't broke, don't fix it' applies here since some folks
seem to aquire transmission problems after changing their fluid....

DoctorBill
__________________
93 Geo Metro, 5sp, HB, 1.0L
t-max is offline   Reply With Quote
Old 12-07-2005, 01:46 PM   #3
DieInterim
AF Regular
 
Join Date: Nov 2005
Location: Uranus, Rhode Island
Posts: 135
Thanks: 0
Thanked 0 Times in 0 Posts
Re: Which is Best Manual Transmission Fluid ?

Quote:
Originally Posted by DOCTORBILL
Reading around about Geo Metro manual Transmission fluid, I get
the feeling that this is a controversial topic.

It looks like it is a toss-up between GM Sychromesh and Redline MT-90.

Any fervent opinions from the early 90's Geo Metro owners ?

Mine is a '93 with 3 cyl 5 speed manual.

It shifts nicely, downshifts nicely and I am wondering if I should
change the fluid as I bought it used and GOD ONLY KNOWS if or
when the fluid was changed.

Maybe 'If it ain't broke, don't fix it' applies here since some folks
seem to aquire transmission problems after changing their fluid....

DoctorBill
Use what the manual recommends.
Now here is the part where I ruffle the feathers of REDLINE fanatics...
dont do it! Lets think this through logically.

First off most users who are having shifting issues - clunking, slow engagement, grinding - already have problems with their synchros. They report and improvement.

If you live in a cold climate and find shifting issues when cold. They report an improvement.

Well the one with cold shifting issues could go to a lighter gear oil in the winter. The others with already fuddy sychros...well they are just buying time with redline.

Synchros work by friction, so essentially one could say they are a cone brake. When you shift the synchro is pushed against the gear whick quickly spins it to synchronized speed and then the shift collar engages the gear. When the syncros wear or have been treated with teflon additive, they lose the ability to quickly spin the gear up to speed before the collar tries to engage the gear. Mismatched speeds = grind.

So how does Redline "Improve" worn/contaminated synchro cones? It does it by increasing friction. In other words its a light oil and the parts rub against each other more instead of a thick oil film that seperates them like standard gear oil offers.

So in short.. sure it will improve shifting, but expect to replace synchros in the near future due to the increased wear. Dont take my word for it, I can point you to many people that swear REDLINE hosed their transmissions. (I disagree, I think that their transmissions were needing service anyway.)

For me, I use clean, fresh, standard gear oil. Heavier in warmer climates, lighter in colder. (Mine is stubborn when its cold; I drive one block in 1st gear and its all ready to go.)

FWIW,
Blake
DieInterim is offline   Reply With Quote
Old 12-07-2005, 02:05 PM   #4
mik13usa
AF Enthusiast
 
mik13usa's Avatar
 
Join Date: May 2004
Location: Pomona, California
Posts: 217
Thanks: 0
Thanked 0 Times in 0 Posts
Re: Which is Best Manual Transmission Fluid ?

standard gear oil in these transmissions is just a bad idea. Period.! The manual may say use GL 4 BUT... The cars originally came with GM synthetic Synchromesh. How do I know? I worked at one of those oil change places for years, many years ago. Any time someone would change the oil to the Manual reccommended they would begin to have problems. It is just like Blake said, the GL is to slick, it does not allow for the proper friction element to engage the gears properly. Again this is only my opinion. And any one who swears that Redline hosed their tranny, I would love to see them personally. I have done years of research about the subject, and have yet to see the transmission ever built NOT perform better with a synthetic Esther based gear lubricant.
mik13usa is offline   Reply With Quote
Old 12-07-2005, 02:07 PM   #5
DOCTORBILL
Geo Metro Lover
Thread starter
 
DOCTORBILL's Avatar
 
Join Date: May 2005
Location: Eastern Washington State, Washington
Posts: 1,616
Thanks: 0
Thanked 0 Times in 0 Posts
Re: Re: Which is Best Manual Transmission Fluid ?

Quote:
Originally Posted by DieInterim
Use what the manual recommends.
.
.
.
For me, I use clean, fresh, standard gear oil. Heavier in warmer climates, lighter in colder. (Mine is stubborn when its cold; I drive one block in 1st gear and its all ready to go.)

FWIW,
Blake
OK.....what you say makes sense.

The Chilton Manual says, "When adding fluid or refilling the manual
transaxle always use GL-5, 80W or 80W-90 weight gear oil."

Any brand better than another?

Is GM Syncromesh gear oil a specifically better oil?

My transmission works well, even at 7 F after a while.
Makes whining noises when really cold until it warms up.
I just start the engine with the clutch in, hold the clutch
in until the engine warms a bit (60 seconds) and slowly
let the clutch out. Nearly kills the idle, but eventually
it warms the transmission enough to not be noticable.

In the summer - works fine.

I just want to MAKE SURE the gear oil is OK. Bought the
car used at 145,000 and don't KNOW if the trans oil was
ever changed. Ever!

Manual Transmission lube shouldn't degrade tho, should it?

Only thing is, if never changed EVER, may have some metal
chips in it from the Factory....


Again - best brand? Other opinions?

DoctorBill
__________________

DOCTORBILL is offline   Reply With Quote
Old 12-07-2005, 02:23 PM   #6
DOCTORBILL
Geo Metro Lover
Thread starter
 
DOCTORBILL's Avatar
 
Join Date: May 2005
Location: Eastern Washington State, Washington
Posts: 1,616
Thanks: 0
Thanked 0 Times in 0 Posts
Re: Re: Which is Best Manual Transmission Fluid ?

Quote:
Originally Posted by mik13usa
standard gear oil in these transmissions is just a bad idea. Period.! The manual may say use GL 4 BUT... The cars originally came with GM synthetic Synchromesh. How do I know? I worked at one of those oil change places for years, many years ago. Any time someone would change the oil to the Manual reccommended they would begin to have problems. It is just like Blake said, the GL is to slick, it does not allow for the proper friction element to engage the gears properly. Again this is only my opinion. And any one who swears that Redline hosed their tranny, I would love to see them personally. I have done years of research about the subject, and have yet to see the transmission ever built NOT perform better with a synthetic Esther based gear lubricant.
Now I am confused.....

So - are YOU saying Redline is OK ? Blake says not...
Are Redline and GM Syncromesh "synthetic" lubricants?
Are they equivalent to each other?

Are they not OIL products? What do you mean "STANDARD" ?

If these Geos originally came with "GM synthetic Synchromesh" in the
manual transmission, perhaps I had best stick to THAT !

I am a retired chemist and know what "Oil" is but not what these
so called 'synthetics' are made of. You said Esters.
Is there a web site that explains the chemical composition of these
goodies?

Transmissions amaze me. I never could understand EXACTLY how
they do what they do - the syncromesh part that is.

And Automatics are an enigma wrapped in a mystery....

Fluid hydaulics! Hummmm....

So, again - which is best...?

What means GL anyway?

If I open my transmission and obtain a small sample of what
it contains NOW, how can I tell if it is Synthetic or OIL based?

DoctorBill
__________________

DOCTORBILL is offline   Reply With Quote
Old 12-07-2005, 02:23 PM   #7
DieInterim
AF Regular
 
Join Date: Nov 2005
Location: Uranus, Rhode Island
Posts: 135
Thanks: 0
Thanked 0 Times in 0 Posts
Re: Re: Re: Which is Best Manual Transmission Fluid ?

Quote:
Originally Posted by DOCTORBILL
OK.....what you say makes sense.

The Chilton Manual says, "When adding fluid or refilling the manual
transaxle always use GL-5, 80W or 80W-90 weight gear oil."

Any brand better than another?

Is GM Syncromesh gear oil a specifically better oil?

My transmission works well, even at 7 F after a while.
Makes whining noises when really cold until it warms up.
I just start the engine with the clutch in, hold the clutch
in until the engine warms a bit (60 seconds) and slowly
let the clutch out. Nearly kills the idle, but eventually
it warms the transmission enough to not be noticable.

In the summer - works fine.

I just want to MAKE SURE the gear oil is OK. Bought the
car used at 145,000 and don't KNOW if the trans oil was
ever changed. Ever!

Manual Transmission lube shouldn't degrade tho, should it?

Only thing is, if never changed EVER, may have some metal
chips in it from the Factory....


Again - best brand? Other opinions?

DoctorBill
Old oil can contain moisture, oxides, and acids that chew at the netal. Even though it may have high lubricity, it can be chewing away on your parts.

Blake
DieInterim is offline   Reply With Quote
Old 12-07-2005, 02:47 PM   #8
DieInterim
AF Regular
 
Join Date: Nov 2005
Location: Uranus, Rhode Island
Posts: 135
Thanks: 0
Thanked 0 Times in 0 Posts
Re: Re: Re: Which is Best Manual Transmission Fluid ?

Quote:
Originally Posted by DOCTORBILL
Now I am confused.....

So - are YOU saying Redline is OK ? Blake says not...
Are Redline and GM Syncromesh "synthetic" lubricants?
Are they equivalent to each other?

Are they not OIL products? What do you mean "STANDARD" ?

If these Geos originally came with "GM synthetic Synchromesh" in the
manual transmission, perhaps I had best stick to THAT !

I am a retired chemist and know what "Oil" is but not what these
so called 'synthetics' are made of. You said Esters.
Is there a web site that explains the chemical composition of these
goodies?

Transmissions amaze me. I never could understand EXACTLY how
they do what they do - the syncromesh part that is.

And Automatics are an enigma wrapped in a mystery....

Fluid hydaulics! Hummmm....

So, again - which is best...?

What means GL anyway?

If I open my transmission and obtain a small sample of what
it contains NOW, how can I tell if it is Synthetic or OIL based?

DoctorBill

API - American Petroleum Institute

GL is Gear lube specification.
So API GL4 has difference properties than GL5.

Example: Some rear ends have copper washers inside them; these need GL4. If you were to add GL5 to this rear end and for some reason the oil reached 200 degrees F, the copper would "melt" away.

Mineral or Synthetics, it does not matter as long as the specifications are the same. Yes synthetics are nice, and very expensive.

You make the call.

Blake
DieInterim is offline   Reply With Quote
Old 12-07-2005, 10:03 PM   #9
bhrollin
AF Newbie
 
Join Date: Oct 2004
Location: Norwich, Connecticut
Posts: 12
Thanks: 0
Thanked 0 Times in 0 Posts
Re: Which is Best Manual Transmission Fluid ?

The owners manual for my 1997 1.0 5 speed metro says to use castrol syntorq. The difference is that synthetics flow at lower temperatures and can take higher temps without breaking down.
bhrollin is offline   Reply With Quote
Old 12-09-2005, 06:31 PM   #10
DOCTORBILL
Geo Metro Lover
Thread starter
 
DOCTORBILL's Avatar
 
Join Date: May 2005
Location: Eastern Washington State, Washington
Posts: 1,616
Thanks: 0
Thanked 0 Times in 0 Posts
Re: Which is Best Manual Transmission Fluid ?

Whilst in Schuck's this morning buying a Bosch O2 Sensor, I bought
three quarts of Valvoline Durablend SAE 80W-90 Gear Oil.

$6.00 per quart. "Synthetic Blend" - API services GL-5, MT-1

Now - everyone tell me I made a Bad Choice.....

It is a synthetic, not all that expensive, and a 'name brand.'

Now if the weather here in Spokane will abate for a while, I will
endeavor to change my gear oil.

DoctorBill

PS - when I bought this '93 Metro, someone had put a turned metal
gearshift knob on the shift lever. 'Bout froze my hand to it when it
got down to 6 F !!!

So I went to a crafts store and bought a 4 inch wood ball, waxed it,
drilled it out and hotmelt glued it to the shift lever.

Works Fantastic! Fits my hand nicely, isn't as cold as a
witch's boob on Halloween, and looks 'neat!' Tubular! Knarlie!
Hey, Man! Bitchin'! .....shows how old I am!
__________________

DOCTORBILL is offline   Reply With Quote
Old 12-09-2005, 07:18 PM   #11
DieInterim
AF Regular
 
Join Date: Nov 2005
Location: Uranus, Rhode Island
Posts: 135
Thanks: 0
Thanked 0 Times in 0 Posts
Re: Re: Which is Best Manual Transmission Fluid ?

Quote:
Originally Posted by DOCTORBILL
Whilst in Schuck's this morning buying a Bosch O2 Sensor, I bought
three quarts of Valvoline Durablend SAE 80W-90 Gear Oil.

$6.00 per quart. "Synthetic Blend" - API services GL-5, MT-1

Now - everyone tell me I made a Bad Choice.....

It is a synthetic, not all that expensive, and a 'name brand.'

Now if the weather here in Spokane will abate for a while, I will
endeavor to change my gear oil.

DoctorBill

PS - when I bought this '93 Metro, someone had put a turned metal
gearshift knob on the shift lever. 'Bout froze my hand to it when it
got down to 6 F !!!

So I went to a crafts store and bought a 4 inch wood ball, waxed it,
drilled it out and hotmelt glued it to the shift lever.

Works Fantastic! Fits my hand nicely, isn't as cold as a
witch's boob on Halloween, and looks 'neat!' Tubular! Knarlie!
Hey, Man! Bitchin'! .....shows how old I am!
Good choice. I laugh at the speed racers who buy the speed stuff and own an econo-box. Even worse add all of the wings and ground effects that actually create drag and reduce the terminal speed of the car. Blumentopft!

Fer shizzle my nizzle.
Blake
DieInterim is offline   Reply With Quote
Old 12-12-2005, 02:56 PM   #12
DOCTORBILL
Geo Metro Lover
Thread starter
 
DOCTORBILL's Avatar
 
Join Date: May 2005
Location: Eastern Washington State, Washington
Posts: 1,616
Thanks: 0
Thanked 0 Times in 0 Posts
Re: Which is Best Manual Transmission Fluid ?

Quote:
Originally Posted by DieInterim
Good choice. Fer shizzle my nizzle.
Blake
OK....I thought I knew how to insert a picture in my "Signature" as
you have been doing - but I don't!

I've got the "Avatar" pic down OK, but I don't know how to include
a picture 'with' my signature file.....

Can you describe HOW you are doing that?

DoctorBill
__________________

DOCTORBILL is offline   Reply With Quote
Old 12-12-2005, 03:10 PM   #13
DieInterim
AF Regular
 
Join Date: Nov 2005
Location: Uranus, Rhode Island
Posts: 135
Thanks: 0
Thanked 0 Times in 0 Posts
Re: Re: Which is Best Manual Transmission Fluid ?

Quote:
Originally Posted by DOCTORBILL
OK....I thought I knew how to insert a picture in my "Signature" as
you have been doing - but I don't!

I've got the "Avatar" pic down OK, but I don't know how to include
a picture 'with' my signature file.....

Can you describe HOW you are doing that?

DoctorBill
Sure!

In the sig line use the [IMG] tags. The pictures I use are linked via the web.

EXAMPLE -

Cheers!
Blake
DieInterim is offline   Reply With Quote
Old 10-07-2015, 02:40 PM   #14
archer973
AF Newbie
 
Join Date: Oct 2015
Location: Friday Harbor
Posts: 2
Thanks: 0
Thanked 0 Times in 0 Posts
Re: Which is Best Manual Transmission Fluid ?

I've come along 10 years after all the other posts looking for an answer to the question, "Which lubricant do I use in my 1996 Geo Metro, 1.0 L, 3 cylinder, 5-speed manual transmission. It seems the prevalent answer here is go with what the manual says. I have a Geo owner's manual, a Chiltons and a Haynes. They all agree the correct lube is GL-5. But in searching the internet I found that this is controversial and I found a couple of documents that sound highly informative and technical and they recommend GL-4 due to the use of yellow metals in the synchros.

Well, I cannot be sure who is the best authority, but I have one more insight I would like to add and I will state up front that this may not be the best source of information, but it does give a twist to the discussion. I was ordering lubricant, Red Line MT-90 (GL-4), from Amazon.com and using their filter to see if my selection was right for my vehicle. What I discovered is, their filter recommends this product for the M42 and M58 transmissions but not the MV2.

Maybe that is why the proper lubricant is an issue for this car. My car has the M58 transmission so I've decided to go with the GL-4, but I base this on a collection of sources, not just the Amazon filter.
archer973 is offline   Reply With Quote
Old 10-07-2015, 04:03 PM   #15
Crvett69
AF Moderator
 
Crvett69's Avatar
 
Join Date: Oct 2004
Location: Bellingham, Washington
Posts: 1,716
Thanks: 0
Thanked 72 Times in 72 Posts
Re: Which is Best Manual Transmission Fluid ?

i have been running syncromesh is all my metro transmission with great results. also when they changed the name to chevrolet metro in 98 they changed the fluid recommendation to syncromesh and its the same transmission as the older ones
Crvett69 is offline   Reply With Quote
 
Reply

POST REPLY TO THIS THREAD


Bookmarks
Go Back   Automotive Forums .com Car Chat > Geo > Metro

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off



All times are GMT -5. The time now is 01:03 PM.

Community Participation Guidelines | How to use your User Control Panel

Powered by: vBulletin | Copyright Jelsoft Enterprises Ltd.
 
 
no new posts