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Muncie SM465

Discussion in 'The Hokey Ass Message Board' started by Gearstix, Jan 3, 2009.

  1. Gearstix
    Joined: Dec 21, 2008
    Posts: 194

    Gearstix
    Member

    Does anybody here have one? Do you like it? Whats the shift pattern with it?
    I can get these for 2-300 bucks... thinking about picking one up but ..

    "The 465 is an intellegently designed and very well-built transmission and remains easy to locate and generally inexpensive to buy and maintain. The strength, relatively short size and the gearing of the transmission make it a good choice for a variety of on-road and off-road situations. It has a very good set of road manners contrasted by its enormous off-road brawn."

    Not sure if it'd be good for a street application..
     
  2. Jay Rush
    Joined: Jan 3, 2007
    Posts: 508

    Jay Rush
    Member

    aren't these a big 4 speed with granny low 1st gear that came in fullsize pickups ?
     
  3. 19GMC63
    Joined: Apr 22, 2007
    Posts: 22

    19GMC63
    Member

    What would it be going in????
     
  4. Gearstix
    Joined: Dec 21, 2008
    Posts: 194

    Gearstix
    Member

    something non-hamb friendly... although I'm considering a body swap.
     

  5. Gearstix
    Joined: Dec 21, 2008
    Posts: 194

    Gearstix
    Member

    yeah, thats why I'm wondering if it'd be any good for something other than a truck or 4wd.
     
  6. RichG
    Joined: Dec 8, 2008
    Posts: 3,919

    RichG
    Member

    They are a good tranny, I swapped the three speed out of my '59 for one back in high school. They are very short if I remember, but also a bit tall? It's been awhile since I screwed with it. The first gear is extremely low also. I helped my brother in law heft one up behind the 396 in his '72 4x4, it takes the torque from that monster, so it's gotta be tough!
     
  7. Gearstix
    Joined: Dec 21, 2008
    Posts: 194

    Gearstix
    Member

    I can deal with a low first gear, but I want some decent speed out of it.
     
  8. RichG
    Joined: Dec 8, 2008
    Posts: 3,919

    RichG
    Member

    Well, you'd have to have pretty short gearing in my mind to make any real speed. 3.55 or numerically lower, at least if you don't want to rev the crap out of your motor.

    The other issue is the range between gears. These are a wide ratio tranny, so you're not gonna get the performance like you would with a car four speed.
     
  9. Gearstix
    Joined: Dec 21, 2008
    Posts: 194

    Gearstix
    Member

    My vehicle has a 3.73 rear end if that helps.

    It has a T-5 in it now... looking for something a bit stronger and something that will bolt up to a v8... my T-5 wont
     
  10. Shifty Shifterton
    Joined: Oct 1, 2006
    Posts: 4,964

    Shifty Shifterton
    Member

    The SM 465 is a great medium duty truck transmission, excellent choice if your priorities are towing or off roading.

    It is not an excellent choice if your priorities are.......

    A. Speed shifting. This is literally a dump truck transmission. Light duty dump trucks, but dump truck nonetheless.

    B. Transmission humps that aren't a focal point of the interior. They're HUGE and disguising them won't be graceful. The original quoted review that considers them compact is comparing them to other medium and heavy truck transmissions.

    C. Weight- unlike that T5, you'll need help installing this one. Know anybody that can bench press 300 lbs? Buy whatever beer they drink before attempting install. Dragstrip traction should improve due to the extra 200lbs on board.

    D. Parasitic power loss. Along with the ability to survive 4x4 clutch pops comes huge heavy internals. Start spinning that input shaft to 6500 rpm and watch it eat a third of your horsepower.

    Just a few things to think about. Good luck

    PS you can disassociate the word "muncie" from this transmission when talking street cars. They share a manufacturer but are a world apart, and using the term muncie is just making you think it's a suitable candidate by word association with M20/21/22.
     
    Last edited: Jan 3, 2009
  11. I might add to what Shifty said, 1st gear is useless on the street, This tranny is usually driven like a 3-speed. In the early 60's they were occasionally used because this gave you a synchronised gear to shift down to (in this case 2nd) for those who liked to only slow to a crawl at stop signs,plus the early 3-speeds were fragile. In '67 the all synchro 3-speed emerged with the added attraction of a lot more strength.
     
  12. propwash
    Joined: Jul 25, 2005
    Posts: 3,858

    propwash
    Member
    from Las Vegas

    Keep in mind - Muncie is a town and transmissions are made there. M20, M21, M22 are all GM option numbers. Of course if you walked into the factory (in Muncie) they could tell you the difference using those numbers, but think about an M40 option.....that's not a muncie trans at all. Not even sure the M465 was made in Muncie. M is how GM denotes transmission options...just like Z is for performance packages and L is engine.

    dj
     
  13. Shifty Shifterton
    Joined: Oct 1, 2006
    Posts: 4,964

    Shifty Shifterton
    Member

    Upon further reflection.....I'd always thought they were manufactured by the saginaw division. :confused: Doesn't really matter, they're still unsuitable for street cars unless you're the Blastolene guys.
     
  14. RichG
    Joined: Dec 8, 2008
    Posts: 3,919

    RichG
    Member

    Well, I used the first gear. 'Course, I had a slinger six, and that low gearing was what I needed to get forward motion...wide gears, long throws, but I did bend the stick up pretty cool. That I bent it putting the cab on without taking the stick off, well...
     
  15. budd
    Joined: Oct 31, 2006
    Posts: 3,478

    budd
    Member

    i had two, one i sold for $75, the other i still have as no one wanted to buy it, times as they are i wouldn't pay more then $50 for one.
     
  16. The SM465 is the updated version of the SM420, which was used through 1967. The SM465 was available into the 1990s. So they should be plentiful in bone yards.

    They are very heavy, it was often a 2-man job to install one, the older trucks had removable floor boards which helped the task. Most trucks had a steep rear end ratio like a 4:56, 5:13 or 5;38. I had one in a 1965 Chevy panel and only used 1st gear for pulling a boat up a ramp or carrying something ungodly heavy.

    Bob
     
  17. junkyardroad
    Joined: Oct 3, 2007
    Posts: 410

    junkyardroad
    Member
    from Colorado

    Advance Adapters has a lot of info about these and many other trannys. They have many different tailshaft length/spline count configurations. Parts are readily available and it is a easy rebuild. SM465s are common in 1/2 to 2 1/2 ton trucks from the late 60's to early 90's. Tremendously strong and durable, slow shifting with a 6.56 to 1 granny which makes them popular with offroaders. I seriously considered putting one in my 54 Ford but decided to use a 700r4 because of the od. I know a guy who lost a finger when his 465 dropped off a jack. I have always been able to do an install bench press style, but if it gets away, move very quickly or it will crack your driveway after crushing your body. You will need a bellhousing with the truck size bearing retainer hole. The case is short, in a long vehicle you may need a 2 piece driveshaft.
     
  18. Gearstix
    Joined: Dec 21, 2008
    Posts: 194

    Gearstix
    Member

    Well what I was looking at came with a bell, I was thinking about buying the transmission complete..
     
  19. bigdreamsnobux
    Joined: Oct 6, 2005
    Posts: 222

    bigdreamsnobux
    Member

    My advice would be to pass, and get somethingmore speed performance related. I had a heavy duty SM465 in a rockcrawler Jeep. My buddy drove it once (he had many muscle cars) and thought the tranny was out of a tractor.

    If you planned on going fast with it, the throws alone feel like about 2.5 feet.
     

  20. old thread but just some more FYI;
    SM420 from 1947-1967(later in special rigs)
    SM465 from 1968-1991
    420 and 465 will not interchange bellhousing. 420 is 4 11/16 center hole and 465 is 5 1/8 or so...
    420 has lower first gear
    both should only be used in truck and 4x4 HD applications.
    HP wont reach your rear wheels for a street rod.
    PITA to change and heavier than your motor... :eek:
    for a car or other non-hauling rig get a m20/21/22 or anything else that came in car or van.
    420 has a 7.06:1 first gear. you wont get from one crosswalk line to teh other(on your side of intersection) before having to shift.... LOL!!!
     
  21. Rooney00
    Joined: Dec 2, 2006
    Posts: 312

    Rooney00
    Member

    Exactly! I had one in a 78 Chevy pickup. Good for that, but heavy and huge. Those trucks had a special floorboard to cover it.
     
  22. trkklr77
    Joined: Aug 28, 2007
    Posts: 1

    trkklr77
    Member
    from galt ca,

    back from the dead.

    465 will handle 2x the hp as any of the car and light truck [t-5, m20-22, t56].
    465 has a slightly faster low gear, 6.55.
    because it has the stupid slow first you can run a stupid fast ring and pinion, 2.73, 3.0, 3.08 with a moderately tall tire and you will not only luanch but carrie speed on the top end.

    they are very slow shifters, particularly from 2-3, but most of you action will be 1-2 which is straight back.

    i drive like a complete dick everywhere in my 4x4[bbc,465,4.56:1] and it took 7 years for me to finaly where mine out, not just driving mind you, gear slamming , tree stump pulling, clutch dumping, rollbacks, and any other action that would leave a side loading tranny gutted out on the asphalt.

    they are big, and heavy, and ugly, and slow but you set it between a big motor and a fast set of gears and it will be the last tranny you swap.
     
  23. 50'custom
    Joined: May 19, 2009
    Posts: 149

    50'custom
    Member

    uh,well then i have a question....i had a 67' chevy long bed...factory 2.02 duble humped 327-4 speed...low first gear(that wined im told that caricteristic)HUGE gap between 2-3 and when i pulled it out it was short-tall top shift,and i didn think it was that heavy...i layed under the truck droped it on my belly side scooted out and stood up with it....what could that have been ? It was strong i know that...i puched that 327 60 over flat tops,shaved deck,as much head work as my local speed shop could do...the whole deal balanced,nice fat cam...then your typical intake/exhaust boosters the thing had hella compresion and would rattle the windows on main street thrue 2 single in dual out flowmasters...and i was hard on that truck after i shortned it into a SW...I MEAN HARD a nail has never been hammered like i did that truck.i finally sold the tranny for a m-20 that i shattered the first day i had it all together and goin agin
     
  24. Shifty Shifterton
    Joined: Oct 1, 2006
    Posts: 4,964

    Shifty Shifterton
    Member

    ^That wasn't an SM465 if you scooted it out on your belly and stood up with it. Sorry, but I've alligator-wrestled a bunch of transmissions and even if you're 275lbs of pure muscle there's gonna be veins poppin to do what you describe with a real 465. In fact doing exactly what you describe put a 275lb friend into back surgery. True story.
     
  25. highboy_04
    Joined: Feb 5, 2006
    Posts: 245

    highboy_04
    Member
    from Kansas

    sm420 that was the last year for them
     
  26. 50'custom
    Joined: May 19, 2009
    Posts: 149

    50'custom
    Member

    i dont know what it was ??? just that i could carry it around....i would probly compair its weight to a turbo 350 it but it weighed a little less than that.I know the truck had the factory engine,but the tranny part is sketchy...a guy new a guy that had a brother that new a guy kina deal....i bought the truck at a farm auction....?????
     
  27. jr9162
    Joined: Sep 8, 2008
    Posts: 247

    jr9162
    Member

    It was a SM420. Smaller but lower 1st gear ratio than the SM465. Very popular in Jeep 4x4 conversions. The one I had (and sold) I took out of a 68 Chevy 3/4 pickup truck. It was behind a 283. All the books say 1968 was the year of SM465 and 307's but I guess GM used up the last of the leftover 283/SM420's early in the 68 production run. The SM420 was used from 48 to 67 (early 68) in GM trucks up to and including 2.5 tons.
     
  28. Gearstix
    Joined: Dec 21, 2008
    Posts: 194

    Gearstix
    Member

    Bringing this back from the dead.
    Would a 465 be any good behind a diesel engine? I can pick these up for $75 with low miles.
     
  29. JohnEvans
    Joined: Apr 13, 2008
    Posts: 4,883

    JohnEvans
    Member
    from Phoenix AZ

    Yep , but remember high gear is 1 to 1 no OD here.
     
  30. 53sled
    Joined: Jul 5, 2005
    Posts: 5,819

    53sled
    Member
    from KCMO

    cummins? cat? vw? more gears are always better, especially with a low revving diesel. saving money on the transmission, only to spend it back in extra fuel costs.
     

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