change of plans re: transmission
 

Just ran into a 3-speed overdrive, never thought I'd find one of these! I think I can buy it for around $200.......hard to pass that up, I think. I's the non- synchro, bout a '60 vintage, but heck, I learned how to double cluch down into first gear years ago :lol:

Plans HAD been to change out the 4-speed for a 700r4, primarily to get the cruising "economy" and lower RPM on the highway.........so this covers the biggest reason for the change.

Been holding off setting the motor in the truck, till I could afford the 700r4...not inexpensive for a well built one! Add in the crossmember change, lockup converter, TV cable, and it's a few bucks more, plus the shifter. (Lokar floor shifter had been planned, since the automatic columns and linkage aren't cheap, either)

This 3-speed means no crossmember change, and I'll probably look around for a second-hand 3-speed floor shifter for the time being, and hope to eventually find a standard column sometime. I'm sure they're more common than the autos. No fooling with the e-brake stuff, either, which surprisingly, is complete original, and working!

downside? well, the DW may not be as excited to drive it, but I can probably get her past that......she used to drive a schoolbus, after all, and they were all standards then! She was looking forward to the automatic in this, but, ce la vie! As for me, 2 pedals, 3 pedals, I don't much care, really! Saving a ton of $$$ interests me!

All in all, this will move the project along faster, since the biggest holdup is having the extra $$$ to do this stuff!

So, a couple of questions:

1) I've read up here on these OD's, and I'm going to need to wire it up,set up a cable lever, (which is not with it) etc to make the OD work, but will it function like a regular 3-speed until I get that done? what about the speedometer, will it connect right up and work correctly? Anything particular I need to look for in a floor shifter, does the seat interfere? Tanks for the help!

Re: change of plans re: transmission
 

DANG! he just called to tell me he sold it!! I shoulda went this morning! :whine:

Oh well, NEVER MIND! (actually, it's still probably a good idea, I'll just never find another for that price!)

Re: change of plans re: transmission
 

The good and the bad...
Those od's are nice--when working properly. I've had 2 vehicles w/them. Install a 2nd dimmer switch in the floor, wire it up to override the governor, use dimmer to actuate at any speed, and have od in each gear--giving 6 gears in all! Get from zero up to hwy speeds w/o exceeding much more than 12-1500 rpm's, depending on rear gear. BTW: They are 70% od, meaning if using a 4.11 gear, when in od, engine sees a 2.88 gear(4.11X70% = 2.88).

Keep in mind, tho', if something like just a solenoid fails, they are nearly impossible to find. I "got rid of" one of those trannies about 2 years ago, telling buyer it had a bad solenoid. Last I talked to him, he still has not found one. (I'm sure he would "dispose of" the trans--altho' shipping would probably be quite much to anywhere due to weight.)

Answering 1-2 of your ?'s: pull out the lockout lever/cable & have a normal 3-speed. Wiring schematics are readily available.

And they aren't the most robust trannies out there!
sam

Re: change of plans re: transmission
 

thanks, luvbowties.
yeah, I've read about these quite a bit, so I know they aren't for beating on.....that's OK, I'm a very gentle driver, (my hot rod days are WAY behind me :lol:) and my engine is a very stock 350. As for the difficulty to find parts, well, since this will require almost no modification to the truck, I guess I'd still have other options, in that event.

Actually, turns out the guy I was hoping to buy it from knew somebody with another one, so he tracked him down, and believe it or not it looks like I can actually buy this one, AND its complete with the wiring and cable, even the lever....still for only about $250. trying to get together on Friday.
For me, this is absolutely a shortcut to on the road, and lower OTR RPM's. My truck has 3:73's

Re: change of plans re: transmission
 

you are probably lucky as the o/d floor shifter linkage is different than a regular trans. special arms to clear the solenoid. had two different trucks with this trans and hooked up to a toggle s/w to shift when o/d. you have to take it out of o/d (pull the cable) to back up (won't go into reverse) also when s/w out of o/d (cable pushed in still) will free wheel, like being in neutral under 25-30 mph. also Saginaw had a all syncro o/d. dont over look the 4-speed that came in some chevy trucks (really a 3sp with 4th an o/d)----have fun

Re: change of plans re: transmission
 

61k10 thanks for the heads up on the shifter......not real clear, is it just the linkage rods that are unique? are you referring to a stock column linkage, also, or just a floor shifter? Ideally, I'd like to eventually change out my column, (4-speed, no shift mechanism at all) but I guess I was thinking for the time being, I could use any aftermarket floor shifter made for a 3 speed chevy...... not so?

I do remember driving a few of these around, back in the 60's I worked in a Chevy dealership, and although not common, they did show up now and then. I recall the "free wheeling" effect, as well as the reverse thing.

sounds like with 3:73's in 3rd OD I'll be turning really low RPM's at 65, but isn't the 700r4 about the same .70:1 ratio in OD?

Re: change of plans re: transmission
 

sounds like with 3:73's in 3rd OD I'll be turning really low RPM's at 65, but isn't the 700r4 about the same .70:1 ratio in OD?[/QUOTE]

Yes, both were 0.70:1. I've used el-cheapo 3-sp floor shifters--one by Sparkomatic and 2nd was outta another truck, unknown source. Rods were such they could be easily bent (curved to clear solenoid, as stated above) to work fine. I always wondered if a really quality shifter could be fitted as easily?

If wired according to orig. GM schematic, there's no issue with reverse--only when we re-wire it so we can get into od at will & forget to dis-engage the switch. Also, can be wired, as from factory, to where it WILL use this reverse idiosyncrasy as a hill-hold control--nice when you feel you need that 3rd foot. It also would electrically make itself shift out of o/d when you floored it, to give a passing gear!

The free-wheeling was a design feature that allowed gears to be shifted 1-2 and 2-3 w/o engaging clutch pedal, as long as you were below approx. 28mph(controlled by governor here)--just let off accelerator, shift, and re-depress accelerator. Have to use care when parking w/o cable pulled out(which merely makes it act like regular 3-speed), or else it may roll. Must use reverse(definitely worked) for park(maybe 1st also, can't remember for sure).

The setup allowed you to take off quicker with the 4.11 and then outrun the same car on top end with a 2.88! Those were the days!

Re: change of plans re: transmission
 

but the stock shifting linkage comes from the other direction, so it's no problem, uses the same as any 3-speed, correct?

funny how those 50 year old memories get a little fuzzy! Fer sure, remember that free wheeling feeling ( in more ways than one!) ;)

Re: change of plans re: transmission
 

Yes, it uses the same as any 3-speed. Did remember that! As far as "50 year old memories", how'd you guess so close?:lol:

Re: change of plans re: transmission
 

well, I was talking about mine, but if the shoe fits.........LOL

turns out the second one needed work, so I passed. Oh, well.

Re: change of plans re: transmission
 

you said, "well, I was talking about mine,"...

So, I can either say "welcome to the club" or else "then, we have a 'commonality of suffering'", huh??
Good to know you're actually out there, or in here(forum), helping another senior "enjoy these bowties". Thanks for the enjoyable association!
sam

Re: change of plans re: transmission
 

"helping another senior" gawd that just sounds awful, don't it? "golden years", my a$$! Then my DW keeps asking if I remembered to ask for my "senior discount"! :lol:

I still think I'll keep looking for the elusive 3-speed OD, though. It seems like a good soution for me, but finding two in a row might have been my complete alotment! :dohh:

Re: change of plans re: transmission
 

Have you thought about using an NV 3500? They plentiful & modern. 1st gear is steep but not granny steep and you get an overdrive. Not sure if they came with mechanical or electronic speedo. You may need to add a hydraulic master cylinder.

Just another option.

Re: change of plans re: transmission
 

Thought about it, but what I like about the early style 3-speed is no mods (crossmembers, e-brake, etc etc) required. If I end up going that route, i'll just do a 700r4, as originally planned.

Re: change of plans re: transmission
 

63burb-----floor shifter only. don't actually remember--something to do with the shifting arms and mounting to clear the solenoid. I had to buy the shifter kit for mine. this was only 45 yrs ago. column shifter will hook right up.

Re: change of plans re: transmission
 

I gave up the search for a 3 speed OD and decided to go with a New Process MY6 (A-883) 4 speed OD trans out of an '83 chevy 1/2 ton. I haven't installed it yet since I'm going to drop the 327 i'm working on in at the same time. But from what i've read, they're a solid OD transmission and a direct bolt in swap if you get one out of a Chevy. You might need to change rear driveshaft length...I haven't gotten that far along yet. and I plan on fabricating a cross member for it to sit on.

Heres some more info on them if you're interested:
http://www.customclassictrucks.com/t..._transmission/

http://www.classicjunkyard.com/new_process_a833.htm

Re: change of plans re: transmission
 

Does anyone know if the earlier Muncie overdrive, 55-57 style would work in these trucks? I realize it will have a long tail shaft, but can I just shorten the driveshaft? My son knows where there's one of these.