FAQ |
Members List |
Social Groups |
Calendar |
Search |
Today's Posts |
#41
|
||||
|
||||
Quote:
|
#42
|
||||
|
||||
Ok guys, edumaction time (for me, that is).
It's my understanding that before the advent of the Muncie, GM used Borg-Warner tranny's (along with Ford). The 3-speed from those days was the T89. Is that the "Dearborn" tranny we're referring to here, or is that something else I'm unaware of?
__________________
|
#43
|
||||
|
||||
Borg-Warner 3-speed
I learned a while back from a member here that the 3-speed manual trannys used back in the very early '60's were, in fact, Borg Warner. Not the same as the Ford/Dearborn Heavy Duty 3-speeds that were in later GM vehicles.
|
The Following User Says Thank You to unclescratch For This Useful Post: | ||
#44
|
|||
|
|||
Quote:
The late 50's - early 60's BorgWarner HD 3 speed was the T-85.
__________________
Buzzards gotta eat... same as worms. |
The Following User Says Thank You to 'ol Pinion head For This Useful Post: | ||
#45
|
||||
|
||||
Thanks guys.
Appreciate the help.
__________________
|
#46
|
|||
|
|||
T-85 very tough, heavy too.
|
The Following User Says Thank You to 421mike For This Useful Post: | ||
#47
|
|||
|
|||
Quote:
Says that in 68 you could get the m13 3speed muncie on both the 325hp and 350hp 396ss cars. Another point, I have no idea what the actual build date of my car was. It could have been a very late 68. |
#48
|
||||
|
||||
I have a 1968 Fbird with a 350 2 bbl, it has a 3 speed Dearborn floor shift which was an option over the base 3 speed manual transmission. The code is DB.
__________________
1967 Firechicken, 499", Edl heads, 262/266@0.050" duration and 0.627"/0.643 lift SR cam, 3.90 gear, 28" tire, 3550#. 10.01@134.3 mph with a 1.45 60'. Still WAY under the rollbar rule. |
#49
|
||||
|
||||
Quote:
Although there are some situations where the RPO code can mean the same transmission, it more often than not doesn't. RPO codes are model year+division+platform specific. As an example, in 1969 any Pontiac (AFAIK) which had the RPO M13 received the Dearborn three speed. Although there are exceptions, typically with GM available equipment changed at the beginning with the model year - there were not rolling changes like Ford ect where depending on the time of year, different equipment could have been installed. That is a good link, I am going to quote a couple points: Quote:
Quote:
Quote:
It appears as though the M13 RPO was quite probably applied to a Saginaw transmission - I had understood that as a matter of pride(?), Chevrolet would not use "Dearborn" parts, and would prefer to use Saginaw, or Borg-Warner.
__________________
1970 Formula 400 Carousel Red paint on Black standard interior A no-engine, no-transmission, no-wheel option car. Quite likely one of few '70 Muncie three speed Formula 400's left. 1991 Grand Am: 14.4 @ 93.7mph (DA corrected) (retired DD, stock appearing) 2009 Cobalt SS: 13.9 @ 103mph (current DD; makes something north of 300hp & 350ft/lbs) Last edited by unruhjonny; 01-22-2021 at 11:26 AM. |
The Following User Says Thank You to unruhjonny For This Useful Post: | ||
#50
|
||||
|
||||
I believe it was also used in 65s, and we shouldn't forget the B-bodies.
|
#51
|
||||
|
||||
/\ The intention I had there was to cite a single model year example of an RPO being used by Pontiac which indicated different equipment than a Chevrolet.
@chevymad: This site seems to be a work in progress may lend to clear matters: http://chevellestuff.net/qd/manual.htm And here's another one: http://macswebs.com/cddemo/66cd/etr/...on/manual.html
__________________
1970 Formula 400 Carousel Red paint on Black standard interior A no-engine, no-transmission, no-wheel option car. Quite likely one of few '70 Muncie three speed Formula 400's left. 1991 Grand Am: 14.4 @ 93.7mph (DA corrected) (retired DD, stock appearing) 2009 Cobalt SS: 13.9 @ 103mph (current DD; makes something north of 300hp & 350ft/lbs) Last edited by unruhjonny; 01-22-2021 at 12:02 PM. |
#52
|
|||
|
|||
Yes, I have a Dearborn 3spd in my warehouse that came out of a '65 GTO. Presumably original in the car. It actually belongs to Pete D from this forum.
|
#53
|
||||
|
||||
From the April '65 edition of Craftsman Service News.
__________________
Ed 1968 GTO (Thanks Mom) 2006 Silverado 2007 Cadillac SRX 2015 Chevy Express |
#54
|
|||
|
|||
Was just looking to see if I could find a pic of the shifter. Web search didn't turn up anything. It was a heavy flat chrome bar much like the hurst, only it had large script on the side that said Muncie. The trans worked pretty well for me, only reason I ever took it apart was to change a bearing in the back. I wouldn't be afraid of one of these 3 speeds for sure. Shifter was very well worn when I got the car, hence the locking 1st and 2nd together. Also this one had a synchro'd first. This is one car I wish I never got rid of, but it's been gone since 93. Last time I researched the trans was 20 years ago, interesting how things change.
|
#55
|
||||
|
||||
...hmmm...Firebird Sprint, 230 HP engine, convertible....I think a HD 3-speed would fit nicely into that scenario....
__________________
|
#56
|
||||
|
||||
Fred, back to your original question, I guess it really depends what 3 speed trans your friend has. Some are certainly durable.
My 72 LeMans GT has the true Muncie M-13 (unruh Johnny points out the side case difference), and it's a stout unit. It was sold as the "heavy duty" 3 speed in 72, and came standard with the GT option. So a step up from the Saginaw. It's a pretty heavy duty cast iron unit. If this is what your friend has, I'd jump on it for $100. While I've never raced it, I have driven it hard on the street behind a the original 350, and now a mild 455 build. The car has 120,000 miles on it, and to my knowledge, the trans has never needed any work. It still works flawlessly. I don't know if I can hurt it. As a bonus, the 3 speeds are more fun to drive on the street, IMO. You still get the fun of driving with the third pedal, and your gear spread is nearly identical to a Turbo 400. The Pontiac torque is quite happy with that gear spread. Hope that helps.
__________________
Eric "Todd" Mitten '74 Bonneville 4dr Sedan (455/TH400/2.93 open) '72 LeMans GT (455/M-13/3.23 [8.5"] posi) '71 GTO Hardtop (400/TH400/3.07 12 bolt posi) ‘71 GTO Convertible (455HO/TH400/3.23 posi) '67 GTO Coupe (455/ST-10/2.93 posi) '67 Tempest Wagon (428/TH400/2.56 posi) Deuteronomy 8:3 |
#57
|
||||
|
||||
There were two Dearborns, at least in 1967, a "DA" and a "DB." The DA is described as the "standard Pontiac 3-speed" whereas the "DB" is described as the "heavy duty Tempest 3-speed." It looks like the DA has a longer output shaft and housing, so it won't fit in a Tempest/Lemans/GTO. Ratios were 2.44, 1.66, & 1.00 w/ 2.33 reverse.
__________________
461 Stroker Built by Me - |
#58
|
||||
|
||||
The longer output shaft would likely be for B bodies. The B body Muncie 4 speeds were also longer than the A body. The D/A designation is for A bodies and the D/B is for B bodies, but that is purely conjecture. I have no documentation, and other than direct experience with both bodies with 4 speeds, that is the obvious difference is the length of the output shaft.
Maybe someone has actual documentation to confirm this? |
#59
|
|||
|
|||
Quote:
Longshaft version is for B-bodies (standard Pontiac) Short shaft is for A (and F) bodies (HD Tempest 3 std) I may be mistaken, but I believe the only difference is the tail shaft/housing with the gearbox itself being essentially identical. |
#60
|
||||
|
||||
Are the gear ratios the same for both trannies?
__________________
|
Reply |
|
|