Re: Marlin twin stick (TS in general)
Date: Saturday, April 13, 2002 12:03 AM
From: Frank Swygert <firstname.lastname@example.org>
Twin-Stick first came out in 1963 and was only used through 65. The
shifter will work with any OD transmission. Twin-Stick is a three speed
standard transmission shifter with a short stick on the right of the
standard shifter that takes the place of the overdrive in/out handle
that was located under the dash of other overdrive equipped cars. No
automatic, and no four wheel drive. The "twin sticks"
(no capitalization!) in a Jeep are the shifter and 4x4 activation
-- not the same thing. All Twin-Stick cars had a console mounted
shifter. The transmission has a bigger gap between 2nd and 3rd
than a normal three speed with overdrive. This was so the trans could
be shifted as a five speed -- 1, 2, 2+OD, 3, 3+OD. The normal 3 speed
with OD was shifted like a four speed. The Twin-Stick shifter had the
kick-down button on the three speed lever to facilitate shifting five
speeds as well. There are more controls with the Twin-Stick system also.
Production 140 6 cylinders 149 287 V8 299 327 V8
Picture donated by Gary NielsenFrank Swygert -- Gulfport, MS Publisher, "American Independent Magazine" (AIM) Supporting all AMC related vehicles, 1902-1987 Website: http://home.att.net/~farna/AIM.html Order a subscription via credit card from our website today!
Message taken from the AMX FILES web site found on links this site.
Twin Stick tranny ANSWERS
Date: Friday, March 12, 2004 05:05 PM
From: Tom Bunsey <TABunsey@aol.com>
You got questions,
I've got answers!
let me say that I have probably had about eight Twin Stick cars over the years
(My first car was a Twin Stick American--64 440 convertible in 1969).
As far as which tranny was used in Twin Sticks, the proper answer is--IT
It depends upon which engine was used.
BTW, they were all manual transmissions with overdrive; the original post
referred to a Borg Warner T-35 tranny, which is an AUTOMATIC.
What AMC essentially did was to put in a much deeper 2nd gear in the tranny, so
that when shifted correctly (going in & out of overdrive) you had the effect of
a 5-speed tranny. Here is how it worked:
1st gear: Normal 1st gear
2nd gear: Normal 2nd gear
engage overdrive to create 3rd gear
3rd gear: 2nd gear in OVERDRIVE
Kick down OUT of overdrive for 4th gear (kick down button on left-hand
4th gear: Normal 3rd gear (not in overdrive)
Engage overdrive for 5th gear
5th gear: 3rd gear in OVERDRIVE
Needless to say, there was a lot of shifting in & out of overdrive to
accomplish all this, but it did work pretty well.
These tyrannies were used with 3.73 rear end ratios in 6-cylinder cars, and with
3.54 ratios in V8 cars.
195.6 6-cylinder cars used the Borg Warner T-96 tranny (4-bolt top cover)
287 V8 cars used the Borg Warner T-86 tranny (I think) with 6-bolt top cover
327 V8 cars used the Borg Warner T-85 tranny (90bolt side cover)
ALL of the above transmissions feature a non-synchromesh first great
The Borg Warner T-85 is a very strong tranny (probably the strongest 3-speed
tranny Borg Warner ever built for passenger car applications). This is the
transmission that Borg Warner modified in 1956 to create the T-10 4-speed, and
we all know about that tranny.
(1) A T-85 will handle any amount of power than any AMC 327 can ever dream of
producing, and probably any reasonable amount from a 390 or 401.
(2) Same input shaft & tranny to bell housing bolt pattern as AMC T-10, so is a
bolt-up to GEN-2 AMC engines by using a T-10 bell housing.
(3) Overdrive with 3.54 gearing gives economy cruise (my Twin-Stick 327 Marlin
regularly gave me 23 mpg at 70 mph).
(1) Non-synchromesh 1st gear
(2) 2nd gear is about 1.9 rather than the convencital 1.5 (or so) 2nd gear in a
typical 3-speed tranny. Gives a real deep second gear.
(3) The Twin-Stick tranny ONLY came with Torque-Tube driveshaft (excepting
1963-65 Americans that had open driveshaft, but only came in the weak T-96
tranny). T-96 tranny is marginal with a 232!
(4) Almost impossible to find the special shift linkage, kick down buttons and
relays necessary to make the system work properly.
(5) Almost impossible to find an actual Twin-Stick setup to cannibalize, or
worse, to find a Twin-Stick Tranny.
(6) These are all cast iron case transmissions, so they are HEAVY!
I suppose that I could "talk" more, but I hate to type. I'll be glad to address
particular issues, however.