Manual overdrive Possible?

Is it possible to have a manual Transmission, but have it set up in gearing to be like an overdrive such as 700r4? If it is, what needs to be done, or what kind of trannys are out there that are good ones to use? Would you use a 4 speed or 5 speed or what? Any ideas. My rear diff has 3.73's so with an OD tranny would be the IDEAL setup. But I have a 4 manual that sucks...

[cableguy0]

there are lots of manual overdrive trannies most are 5 speeds. probabl going to set u back over a grand to get a good one but they are available

[cdowns]

in nascar they use 4speed trannys with overdrives mostly they're tremacs so i guess you could have one built custom for you i'd expect the price to be real high 3-5thousand but there's a few guys on the board that have gone for the richmond 5or 6 speeds i think they run around 2G's

[Longhorn Man]

Huck has done a pretty sweet hyd clutch 5 speed set up out of a truck from the 90's. I drove his rig and I must say it is pretty sweet.
I would stay away from the T-5 trannys, they like to scatter when you give them too much power, especially if it is in a brick like a truck. (ever wonder why the Camaro/Trans-Am was never offered with a 5 speed and a 350?)

[Huck]

I put in a 5 speed out of a 96 chev 1/2 ton truck. Don't know how strong it is as I don't race it but~~~~it pulls great in every gear and that overdrive 5th give me 20+mpg on the road. Only problem is the lack of a speedo hookup as the later trans are all electronic sensed speedo's so I use the tach. Paid $650 for the trans with everything. Needed driveshaft shortened but other then that---pretty easy.

I was talking to a guy about some tranny's and he wanted to know what I needed as in short or long tailshaft, and large or small diameter.... I don't have a clue what hes asking? Any ideas?

[Class of 69]

I bought a brand new 13 speed with over drive in April for $6,000.00. New design required a new clutch cover, and output yoke, but driveshaft length was the same. Oh, yeah! That was in my Pete! You probably don't want a trans that weighs 900 lbs!

[jhwkns]

Here is what I'd like to do.

[1969 GMC]

i'd like to get a Clark 5 speed OD out of an older GM medium truck and pop it right on, then figure out some kind of divorced t-case assembly. might have it regeared, as the best OD those old Clarks seemed to have was 21%. it would be just like an sm465, big clunky shifts and a granny low 1st, except with a 5th gear.

[jimfulco]

jhwkns, "Shefron" at the www.hotrodders.com board recently did that Saginaw conversion. Do a search of the transmission section for "saginaw" & look for his name. Might get a few tips. Those OD units are rare these days.

[jhwkns]

Thanks Jim

[Project1970]

You've got a few options:
1. T-5, if you feel like doing it over and over and are a really cheap bastard
2. Tremec TKO, which is nifty because of its multiple shifter positions, but is so pricey for a five-speed that it doesn't really make sense anymore.
3. T-56. 6-speed and even the weakest variant (the 1993 Camaro unit) is plenty strong for the trucks. They require either a) the truck to be converted to hydraulic clutch or b) the tranny to be converted to mechanical clutch, however. A mechanical speedo drive is available for them. They're also available aftermarket, all set up for the swap, but are pricier ($3k or so)...the bonus is you get the Dodge Viper unit instead, which is obscenely strong!!!
4. Richmond 5 or 6 speed - ask Crazy Longhorn about this one.
5. Late-model truck NV4500 or whatever it is. I don't know much about that swap.

[a71CustomDeluxe]

If you can afford it, this is the way to go...

http://www.gearvendors.com/

[palallin]

Originally posted by Project1970
5. Late-model truck NV4500 or whatever it is. I don't know much about that swap.

I have heard (but never seen for myself) that this swap is fairly straight-forward.

[1967LWBstepside]

You wouldn't happen to have a New Process 4 speed with overdrive in it now would you? I had one for a while -- shifted well but didn't work well in the long run (bearings wore out quickly).

[67Fleetsidedream]

Stay away from the gearvendors overdrive unit. They are good units, but too damn expensive. You could by a brand spankin new tranny for the price of one of those.
T-5 If it is from a V-6 forget it. If it is from a V-8, think twice. They will work but are VERY VERY weak.
T-56 Very good tranny. It is the same tranny that they put in the Dodge Viper, Salleen Mustang, The new Corvette C-4, C-5 and C-6 and many other vehicles that I can not think of at the moment.
I have one in my truck and am very pleased with it.

[Project1970]

67Fleetsidedream...do you happen to have a pic of your shifter and how it sits in your cab? That was my only main turnoff to trying to save enough cash for a T-56 instead of a 700R4...while I absolutely LOVE the T-56 (my brother's 1994 Z28 has one, of course...with a modified (bushing-free) shifter it's a thing of beauty!) I don't like the idea of having mile-long throws just to keep the shift knob up high.

Of course, if there's a way to get the shift knob up there and still keep decently short throws...well, my '70 may eventually go back to a manual, just with twice the gears it shipped with!!!

x 2 hehe

[67Fleetsidedream]

I don ot have pic but I can tell you that the shifter location on my tranny was moved up to the second hole closest to the bell housing on my tranny. It comes out exactly where a SM465 would. I made a "make do shifter stick for mine" and you are right it has about a 7-8 inch throw.
The only way that I can think of to get the shift throw down is to some how raise the shifter approx. 4 inch off of the tranny thus raising the pivot point. Any other ideas?

[crazy longhorn]

Originally posted by 67Fleetsidedream
Stay away from the gearvendors overdrive unit. They are good units, but too damn expensive. You could by a brand spankin new tranny for the price of one of those.
T-5 If it is from a V-6 forget it. If it is from a V-8, think twice. They will work but are VERY VERY weak.
T-56 Very good tranny. It is the same tranny that they put in the Dodge Viper, Salleen Mustang, The new Corvette C-4, C-5 and C-6 and many other vehicles that I can not think of at the moment.
I have one in my truck and am very pleased with it.

[crazy longhorn]

Originally posted by 67Fleetsidedream
Stay away from the gearvendors overdrive unit. They are good units, but too damn expensive. You could by a brand spankin new tranny for the price of one of those.
T-5 If it is from a V-6 forget it. If it is from a V-8, think twice. They will work but are VERY VERY weak.
T-56 Very good tranny. It is the same tranny that they put in the Dodge Viper, Salleen Mustang, The new Corvette C-4, C-5 and C-6 and many other vehicles that I can not think of at the moment.
I have one in my truck and am very pleased with it.

The vendors O/D is a good unit, but i do agree that for the money you can be aftermarket on the stick trans. The richmond 6 spd was roughly $350-400 more than a vendors unit, & is basically a close ratio box , with 1 lower & 1 higher gear ,as compaired to the old "rock crusher" Muncie. The 4 spd truck trans, altho pretty tough, leaves a lot to be desired in gear ratios. You can bolt the richmond to the stock bell, & the lenght is the same as a 400 turbo (trans + bell). The richmond also takes the 400 turbo slip yolk. The auto crossmember that I am running needed mods to fit the trans mount, but I had no driveline mods, as I was running a 400 t before the swap. I cant say for sure on the cab tunnel(mine was modified to fit the 400 T after a minor body drop.......that Richmond does have some "girth". As far as shifter location, mine would not fit a bench seat, but i am running in I6 location with the smallblock. it was a bunch of bucks.....but lots of fun(old "farm truck", with an attitude ) The wifey may not agree, but IMO , worth every dollar spent. Good luck,crazyL

[67Fleetsidedream]

old "farm truck", with an attitude

I feel the same way.