I think this is what you were looking for.
Terry Stellman
1949 3600
Missouri City, Texas
> -----Original Message-----
> From: SDCole [SMTP:sdcole@speedfactory.net]
> Sent: Friday, December 11, 1998 6:19 AM
> To: oletrucks-l@teleport.com
> Subject: TRUCK:: My view on transmissions...
>
> I've done a bit of research over the years on modern OD manual
> transmissions - both to put behind a 235 and a small block.
> I probably have some bogus info, but I've put my experiences in
> where I have it. Keep in mind this list doesn't include non-overdrive
> transmissions.
>
> I think we need to incorporate what we know/have heard into a
> Transmission/Drivetrain FAQ of some sort. I'll do it if y'all'll
> (southern double-contraction) give me a hand with info collection...
>
> Here's what I've discovered:
>
> Borg-Warner T-56 - (6-speed, double OD - Camaro, Vette):
> - standard car-like gear ratios, with OD 5th and 6th.
> - strong
> - without bellhousing
> - integral shifter
> - shifter too far back and awfully short. Truck with a bench seat
> would be problematic.
>
> Borg-Warner T-5 - (5-speed OD, Camaro) :
> - standard car-like gear ratios, with .75 OD 5th.
> - same as above but marginal for a 350 unless
> you get the "world class" version. I doubt it's reliability in
> a heavy truck with abuse or heavy loads (see NV3500 below for
> definition of abuse)
>
> Borg-Warner T-5 (5-speed OD, S-10 truck) :
> - standard car-like gear ratios, with .75 OD 5th.
> - without bellhousing
> - integral shifter further up the trans body - good for a truck/bench
> - would work behind a 6, but too weak for a 350, particularily in
> reference to heavy trucks, abuse, and loads.
>
> New Venture NV3500 : (GM 1/2 ton 5-speed OD, 1988-up)
> - car-like ratios, except that 1st is a little lower. You probably
> would take off in 2nd if you had 3.73 or 4.11 gears. OD 5th.
> - with bellhousing (Chevy pattern)
> - hydraulic clutch (plastic! slave cylinder, located on passg-side)
> - integral shifter (long, truck-style, mounted amidships)
> - I had one of these in a '89
> GMC 1/2 ton with a 350, towed a 1970 model 30ft travel trailer
> periodically (HEAVY!), abused it (rocking to get unstuck, dumping
> the clutch, speed shifted during stoplight contests, etc), and never
> had a problem. Was told by a transmission
> tech that a common cause of failure with this trans is when ATF is
> put into it during a fluid change instead of the ATF-looking
> "special" GM oil (specified in the owner's manual).
> I just put in a 50/50 mix of ATF and SAE30 weight per his
> recommendation. Was still OK after 3 clutches and 170,000 miles when
> I traded it in. As always, YMMV.
> - Would be my choice if I were going with a mild-350 combo. Big block
> would grenade it. Big sticky tires and good traction (rare in a
> pickup truck unless you put cement bags in the bed) and dumping
> the clutch might do it too.
> - OK for stoplight drags. 1st was a little low for my sub-5000 RPM
> stock 350 and 3.42 gears. would work good with 3.23's or 3.08's.
>
> New Venture NV4500 (5-speed OD - 3/4, 1 ton trucks (1988-up)):
> - without bellhousing
> - "granny" 1st gear. OD 5th.
> - A favorite among offroaders for double-low 1st gear for crawling and
> OD 5th to make up for low gears on the highway.
> - truck-like shifter mounted midway on the trans. Good for bench seat
> - Extremely Tough. GM put them behind 454's in 1-ton duallys.
> - wouldn't be good for "stoplight drags" because only 2nd,3rd,4th
> would be useful in racing. (unless you have a big-block ;>)
>
> Eaton/Fuller/Clark 280 series transmission (1 1/2 ton- up trucks???)
> model 280VO
>
> - Read about this one in an offroad magazine
> - without bellhousing
> - top truck-like shifter mounted midway
> - Big, heavy, bomb-proof, cast-iron
> - 6.99 "granny" low 1st, .8 OD
> - supposed to be cheaper and easier to acquire than NV4500
> - This trans is probably related to the Clark 5-speed I had from a '51
> GMC 2.5 ton behind my 235 for a while. Had a granny 1st and non-OD
> 1:1 5th. Pretty good spread of gears. Had 1 major problem,
> though:
> UNSYNCHRONIZED. Can you say double-clutch? If it had a OD 5th and
> synchronizers, I'd still use it. Weighed about 250 lbs.
>
> There's also the Borg 4+3 used in the Corvette for a while, but I
> don't know specifics other than it'd have the same problems with truck
> use as the T-56.
>
> Any experience with the above info would be appreciated - I'm still
> compiling info, but since I live in the city now (Atlanta), I'm
> probably going to end up with an automatic ;<
>
> -Dixon Cole
> sdcole@speedfactory.net
> '54 3100
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