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To OD or not to OD that is the question

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vping

vping

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Ya'll know (mebee not) that the '74 GT parts car I inherited had an OD in it. The PO stated that the mileage on the clock was legit at 42K. (she gave me the car why lie?) The car was a loss but I kept almost all of the parts I could that were salvagable one being the OD. The roadster I have now is in the process of a good cleaning out of the engine bay, re-painting most of the parts and re-building or re-placing what I can. As of this moment I basically have a block and head sitting there waiting for paint.
The question is, should I just go ahead and pop out the engine & trans and swap the Trans for an OD? Both Trans' are of unknown condition other than what was told to me.

The 74 GT supposedly had 42K the 74 Roadster supposedly has 85K. Compression test is positive on the 85K engine. Do I take the chance with an unknown OD Trans. I figure I have just as good odds of leaving the 4 speed in it so why not switch?

So far this is what will be done or is done.

New Waterpump on the way.
Carbs are decent from the parts car and 95% gunk free.
All brackets and covers re-painted
All brackets and covers receiving new gaskets.
Engine scheduled for re-painting
All hoses replaced.
Pertronix awaiting install.
New cap & wire awaiting install.
NGK plugs awaiting install.
Peco exhaust on the way and will be installed.
New Superlights installed.
New Dunlop 195/60 R14's installed.
Full car Urethane bushing kit on the way.
New Gas Tank received - etched primed & Painted.

What say ye?

I listed all what is to be done or is done just to show where I am at so far. Brakes sill need to be addressed but I have all the rebuild kits and new pads are on the way. Ditto on the clutch.
 
All said and done, I doubt I'd ever keep a B long-term without O.D. If it's a 50-50 proposition between the 2 trannies, I say go "OD!" Besides, if you put in the other unit, you'll always wonder if the the OD is any good anyway. If you put the OD in first, you won't care if the 4 speed is good.

IMHO - Adam
 
Even if the OD is shot, the rest of the gearbox will work. Take off the inspection plate and look inside the thing. If the gears look fresh, put it in the car. It's surely better than a gearbox with double the mileage on it, assuming both were taken care of equally and neither rebuilt.

Personally I recommend sending the OD gearbox to Quantum for a rebuild. But it's a matter of budget whether or not you want to do that. You can take your chances and worst case, you have a non-OD gearbox with a dead 20-pound non-functional OD unit mounted on the back.
 
The late model OD units are almost bullet proof! I'd inspect it for interior cleanliness, put in new oil and run it! 10 to 1 it's in good condition. For a cruising car, you'll be glad you did. JMHO. PJ
 
If "ditto on the clutch' means you are pulling it for a new plate, you will probably have everything out and ready to replace anyhow, so I would definately put in the OD tranny when you reassemble. If not, you will regret it!
 
Quantum's website has bee unavailable for several days now, I've been trying to reach them. Anyone got their phone #.
 
Hmmm, if i were you I would go with the non OD tranny. I am sure some kind hearted forum member will take that troublesome OD off of your hands. /bcforum/images/%%GRAEMLIN_URL%%/wink.gif
 
Steve_S said:
Even if the OD is shot, the rest of the gearbox will work. Take off the inspection plate and look inside the thing. If the gears look fresh, put it in the car. It's surely better than a gearbox with double the mileage on it, assuming both were taken care of equally and neither rebuilt.

Personally I recommend sending the OD gearbox to Quantum for a rebuild. But it's a matter of budget whether or not you want to do that. You can take your chances and worst case, you have a non-OD gearbox with a dead 20-pound non-functional OD unit mounted on the back.
Click to expand...

20 lbs. There goes all that weight i've been shedding lately.

I feel confortable with switching them out. Now if I'll pulling the engine, I might as well also replace the clutch - be stupid not to. While I have the engine out what should be done to that, other than a total rebuild to give it more pep and longevity. Again supposedly well taken care of and maintained during it's 85K life. I don't want to spend a fortune or a lot of time with it at this time.
 
<div class="ubbcode-block"><div class="ubbcode-header">Quote:]20 lbs. There goes all that weight I've been shedding lately.[/QUOTE]
Not when you factor back in the tail piece you remove to install the overdrive. Besides, some weight is good weight. Otherwise you'd be missing a lot of pieces that make the car nicer to drive. /bcforum/images/%%GRAEMLIN_URL%%/wink.gif
 
Thanks. I have that link from you when we spoke about the D type. Speaking of D types, is the Trans for a D type the same from day one and you need to add the D type overdrive unit or is the base trans specific to the D type? Does that make sense?
Can you obtain parts for the D type? Someone has offered me parts for the OD unit but not sure if I should take them. I have a D type Trans but not sure if I can just as the D type OD to it.
 
D-Type refers to the overdrive module, not the gearbox itself. You either have a 3-sync, 4-speed gearbox or you have a 3-sync, 4-speed gearbox with D-Type overdrive. Later gearboxes came with LH-Type overdrives which are a bit more sturdy although heavier, just like the transmissions they mate to (4-sync).

If you want to install a D-Type overdrive to a 3-sync gearbox, you also need the mainshaft from an overdrive box (shorter than non-OD), as well as various other smaller bits.
 
I got it now. Thanks. So the parts might be worth taking but I would still need to find a mainshaft if he does not have one. I have a 3 sync in the garage and was keeping it for the 67 if I ever wanted to put it back in. The GT currently has a '68 trans in it. The OD for the 74 is an LH.
 
If the D-Type OD is a complete gearbox then you already have the main shaft. If it's just the OD module and there's no shaft sticking out of the front of it, then you need one and they aren't cheap. Quantum can probably sell you a used one for a price. Also, you need both the OD module and the intermediate housing. Without the intermediate housing you're SOL. Usually the two are always together but if someone separated them, then you will need find that, too. Find a photo of an OD gearbox and you will see what I mean.
 
I don't have a D type, just a 3 Syncro. I'd need a lot of parts if I wanted to make it an OD.
 
No not a D type just the three synchro. That's why I asked about the D type parts this guy has. Should I tke them or will they just collect dut in my garage like they do in his?

Oh and I think I will be pulling the 74's engine and swapping out the Trans. on Saturday.
 
Depends on the price. If it's free I'd take them just for giggles. If it's cheap, I'd probably still take them if you plan to convert the car some day. If he wants a premium, pass on it. You can always find a complete gearbox if you're going to pay full price anyway and then you have all the hard to find and expensive extra bits.

If it's free or cheap and you don't want it, I'll take it for parts. /bcforum/images/%%GRAEMLIN_URL%%/smile.gif

Oh, and remember that converting to OD means a complete gearbox rebuild. You don't just slap it on the tail of your existing one. Everything comes out and gets refurbished.
 
That I'd do for sure. In the case of the '74 with low miles, I'm going to take my chance. If you smell the fluid of an OD will it tell me anything? What should I refill is with 20/50? I know 20/50 for the standard just not sure about the OD. Are there 2 filling points?
 
Smell won't tell you anything unless it's the wrong oil. Refill with your choice of either 20W-50 or straight 30W. 30W is recommended by the manual and by Quantum Mechanics, but people have been using 20W-50 for years without issues. Your choice.

LH-Type OD shares oil with the main gearbox, so one filling point and one drain.
 
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