4 speed simple question......
Thread Starter
Instructor
Joined: Mar 2006
Posts: 127
Likes: 0
From: Miami FL
4 speed simple question......
i asked before along with some other questions but no one answered so. what fluid do you guys like to use on your 4-speeds???? i plan on changing all the fluids in the 76 this weekend and wanted to know what to buy for the tranny..
i remember on my TKO it only liked GM syncromesh stuff. so just asking...
tks
i remember on my TKO it only liked GM syncromesh stuff. so just asking...
tks
Team Owner
Joined: Nov 2004
Posts: 20,708
Likes: 25
From: Sorrento Italy
i asked before along with some other questions but no one answered so. what fluid do you guys like to use on your 4-speeds???? i plan on changing all the fluids in the 76 this weekend and wanted to know what to buy for the tranny..
i remember on my TKO it only liked GM syncromesh stuff. so just asking...
tks
i remember on my TKO it only liked GM syncromesh stuff. so just asking...
tks
i have a t-10 on a 575hp powerplant, anything less then a top brand fully sintetic 90 won't do.
Drifting
Joined: Sep 2006
Posts: 1,259
Likes: 2
From: MS
Do NOT use the GM Syncromesh fluid on any Muncie or Warner 4-speed tranny.
GM says any GL-4 or GL-5 90W, but I would rather stick with a GL-4 80W-90 lubricant such as Redline MTL.
GL-4 less corrosive to soft metals.
GM says any GL-4 or GL-5 90W, but I would rather stick with a GL-4 80W-90 lubricant such as Redline MTL.
GL-4 less corrosive to soft metals.
Pro
Joined: Dec 2006
Posts: 665
Likes: 0
From: wilmington nc
I think that"s supposed to read only use gl4 do not use gl5 in a muncie check out the chevelle forum to see this post in it"s entirety. It"s a sticky over there, i think it eats up your scynorizers!!!!!!
Burning Brakes
Joined: Sep 2006
Posts: 851
Likes: 10
From: Palm City, FL
But I'm gonna watch this thread to see what the consensus is now. Hopefully I dont have to change my fluid again
Let the debate begin.... again.
Drifting
Joined: Sep 2006
Posts: 1,259
Likes: 2
From: MS
The oldest Corvette owner's manual I have is from a 71 and it is right there in the manual that the manual tranny calls for GL-5. Now I do agree with you about the GL-4 and also don't know what the differences are between GL-5 today and GL-5 35 years ago, so that is why I like the Redline MTL. It is defintely a non-corrosive GL-4.
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Thread Starter
Instructor
Joined: Mar 2006
Posts: 127
Likes: 0
From: Miami FL
thanks for all the replies, Redline MTL sounds good, as i used their oil and gear oil in my last 5.0 mustang with great success. thanks guys!!!!! i'll try and take some pics of the work this weekend just for fun
Le Mans Master
Joined: Dec 2003
Posts: 5,727
Likes: 38
From: Fremont CA
Friends DONT! let friends use MTL in Muncies and T-10s! (its TOO thin!) Use Torco or Richmond gear oil if you like you Muncie or T-10 4 speed. I use Redline "shockproof" 90-250WT but, I recently found that it is acidic and attacks brass synchro blocker rings. I have a good friend Dave Helinger at Corvette Repair who can go on for hours on how bad most modern oils are in the old 4 speed. Dave has repaired a few Muncie transmissions for Auto-Gear because of customes using the wrong lube and wrecking the synchro blocker rings.
Team Owner
Joined: Jul 1999
Posts: 65,492
Likes: 230
From: Orange Park Florida
I know lots of you may laugh and say it's not good, but I had over 20k miles on a well used Muncie that was hard shifting....so I put 30w Mobil one syn oil in there, shifted like a dream then....lasted pretty good, no wear noticeable....
I did read long time ago that newer trannies used ATF for fill, and my reaction was, hell, they do that, a gearset is a gearset, only so many ways to make a stick shift box.....and did the engine oil trick....
not as thin as ATF, but hey, it shifted SO much easier,.....
I did read long time ago that newer trannies used ATF for fill, and my reaction was, hell, they do that, a gearset is a gearset, only so many ways to make a stick shift box.....and did the engine oil trick....
not as thin as ATF, but hey, it shifted SO much easier,.....
Melting Slicks
Joined: Sep 2001
Posts: 2,068
Likes: 1
From: Gig Harbor WA
Redline would be good and yes Syncromesh only in a TKO, but a TKO only
I used plenty of redline in my super T10, but I wanna say I used Lucas too. I know I've been using it in my diffs on the race car, street rod outboard motor lower unit (OMC 300 HP V8)
Does Lucas make a Manual tranny flluid?
if not then definitely Redline. I used redline Power steering fluid too.
I used plenty of redline in my super T10, but I wanna say I used Lucas too. I know I've been using it in my diffs on the race car, street rod outboard motor lower unit (OMC 300 HP V8)
Does Lucas make a Manual tranny flluid?
if not then definitely Redline. I used redline Power steering fluid too.
Melting Slicks
Joined: Mar 2005
Posts: 2,838
Likes: 10
From: Austin TX
I have two Autogear Muncies, and George at Autogear (chief engineer) highly recommends the use of conventional 80-90w with a sub-spec of MT-1 which is good for the yellow parts. Valvoline 80-90 has this sub-spec,..Castrol and others don't. He says synthetics are too slippery and the synchros won't mesh as well. You might give him a call if you're running a Muncie,..good guy.
www.autogear.net
Also,..it's thought a synthetic will leak before a conventional lube.
www.autogear.net
Also,..it's thought a synthetic will leak before a conventional lube.
Last edited by 73, Dark Blue 454; Feb 9, 2007 at 02:25 PM.
Drifting
Joined: Sep 2006
Posts: 1,259
Likes: 2
From: MS
Friends DONT! let friends use MTL in Muncies and T-10s! (its TOO thin!) Use Torco or Richmond gear oil if you like you Muncie or T-10 4 speed. I use Redline "shockproof" 90-250WT but, I recently found that it is acidic and attacks brass synchro blocker rings. I have a good friend Dave Helinger at Corvette Repair who can go on for hours on how bad most modern oils are in the old 4 speed. Dave has repaired a few Muncie transmissions for Auto-Gear because of customes using the wrong lube and wrecking the synchro blocker rings.
The MTL is about an 85W on the high side and is only slightly thinner than the MT-90 which is a true 90 weight. GM calls for an 80 or 90W so either one could be used.
http://www.racerpartswholesale.com/redtech4.htm
Le Mans Master
Joined: Mar 2004
Posts: 7,463
Likes: 1,485
From: Little Rock AR
I did a swap to Royal Purple synthetic gear oil and it does not shift as well, makes more noise and leaks. This is a low mileage factory build Muncie. I will go back to the conventional 90W that I used in the first place. I bought a gallon when I filled it the first time. 
This is real inexpensive - It works great - Why jack with it?
-Mark.
This is real inexpensive - It works great - Why jack with it?-Mark.
Racer
Joined: May 2006
Posts: 264
Likes: 0
From: Fort Myers, Fl / St. Paul, Mn
I did a swap to Royal Purple synthetic gear oil and it does not shift as well, makes more noise and leaks. This is a low mileage factory build Muncie. I will go back to the conventional 90W that I used in the first place. I bought a gallon when I filled it the first time. This is real inexpensive - It works great - Why jack with it?
-Mark.
This is real inexpensive - It works great - Why jack with it?-Mark.
Le Mans Master
Joined: Mar 2004
Posts: 7,463
Likes: 1,485
From: Little Rock AR