3 on the tree

[tinman64]

I've got a 64 1000 with a three speed column shift,the trans seemed to up shift OK but down shifting was impossible,the only way to down shift was to come to a complete stop then it would free up.The other day I decided to try to adjust the shift linkage under the hood,again it up shifted not too bad but this time it went into 3rd and now it won't release.I have disconnected the shift rods,tried moving the arms at the trans,nothing moves,I don't want to break anything but the thought has crossed my mind,any words of wisdom out there or shall I just look for a bigger hammer.Any help would be appreciated.thanks. Dave

[raycow]

Save the hammer for something you don't like.

This is highly unusual, but you may have jammed the interlock inside the side cover. You can drain the transmiision oil and unbolt the cover to take a look.

If the interlock is free (that is, you can move the shift arms with the cover off the transmision) try shifting the 2-3 shift sleeve into neutral. Just use a screwdriver between the sleeve and the input shaft gear. If the sleeve won't move, you have something binding inside the transmission and it will probably have to come off the bellhousing for further disassembly and inspection.

Ray

[tinman64]

Thanks for the info Ray,I'll give it a try,I'm still on the fence on the OD tranny,I hate the idea of cutting a hole in the floor for the shifter,if this 3 speed doesn't work out it may be just the push I need to go to the 4 speed.

[raycow]

Originally Posted by tinman64

I'm still on the fence on the OD tranny,I hate the idea of cutting a hole in the floor for the shifter.

I don't like cutting a hole in the floor either. Just to clear up any possible confusion, if you go with the SM318 w/ Borg Warner overdrive you can keep the column shift. The 4 speed A-833 and 5 speed T-5 will both require a hole in the floor.

Ray

[melmashman]

Hi Ray,

I seemed to have lost the link to the Overdrive resource. I think it would be a great addition to my 1965 305e truck/camper.

Any advice you can provide in obtaining & installing one would be appreciated.

Thanks,
Mel Mashman

[raycow]

Originally Posted by melmashman

I seemed to have lost the link to the Overdrive resource. I think it would be a great addition to my 1965 305e truck/camper.

Any advice you can provide in obtaining & installing one would be appreciated.

Hi Mel -

I think this is the link you are asking about.
http://www.stovebolt.com/ubbthreads/...&Number=925247

If that guy's offering is already sold, you could try looking on ebay and craigslist. Other possibilities would be some of the Chevy car and truck forums. They often have a "for sale" and "wanted to buy" section. You could start with Chevytalk, but I know there are others too.

Installation is very straightforward if you have a SM318 in your truck now. The O/D transmission will fit your existing bellhousing and clutch. The worst you would have to do is replace the yoke or shorten the driveshaft. You will also need a manual control cable for the lockout lever. An ordinary choke or throttle cable of suitable length will work, but the real O/D cables are a little heavier than that. Any truck or tractor supply outlet should be able to fix you up with a cable

I will be happy to help you with the wiring when you get to that point, but the electrical hookup is actually pretty simple.

Ray

[melmashman]

Hi Ray and Others,
I am actually getting closer to doing something to the transmission on my 1965 GMC Truck/Camper with a V6 305e and three on the column. My understanding is that it is a 3/4 ton truck with a 1 ton rear end.

I found a shop that specializes is transmission changes for older trucks in Tucson. Here is my need: I plan on doing some cross country trips and even returning to Alaska from Arizona. I also will be taking many short trips in Arizona. Of course there will be some mountain driving, but I can do that at low speed. I am not looking for great gains in mpg, just the ability to not be a traffic hazard on interstates.
Currently it is geared to go up ANY mountain, but seems like it is going to explode at 55mph. It would also be nice to have a synchronized 1st gear.

I think a 4 or 5 speed transmission would be a wonderful way to enhance the engine's life if I plan on going 65mph max. I am willing to cut a hole in the floor. I am also willing to change the rear end gear ratio. I know that a simple overdrive would be a solution, but I wonder if the 4 or 5 speed would be a better match for my long term needs.

I would like to be reassured that a 4 or 5 speed is really designed to handle the load of a camper. I don't really need an automatic. I plan on avoiding city driving.

Remembering that I have a pretty heavy camper on it, is a 4 or 5 speed recommended? The transmission would be rebuilt and a new clutch would be inserted (the old one has over 100K on it). I would prefer the 5 speed if it makes sense. Does it make sense? Also, what specific transmission should I be seeking.

Thanks for any advice you can provide. I value it!
Mel

[raycow]

Addition of the camper changes things somewhat.

The SM318 and T5 are rated for only about 6000 GVW and might not hold up satisfactorily in the long run with the camper. The A833/MY6 overdrive 4 speed is quite a bit stronger and would be a good choice if you don't need a 1st gear much deeper than you have now with the SM318. If you need a grannny 1st gear, you would want something like an NV4500. This is a truck 5 speed with a granny 1st and an overdrive 5th.

The A833 is a relatively easy install. If you get the right one (next paragraph) it will bolt directly to your stock bellhousing after you open up the center hole to 5.125". This is a simple job that any machine shop can do. It is the same length as a "long" SM318 (about 21" from the bellhousing face to the rear seal) and has a 27 spline output. If you have a long SM318 now, the most you will have to do is change the yoke. With a "short" SM318 (about 16"), you will need to shorten your driveshaft.

The one gotcha is that the GM version of the A833 was made with two different bolt patterns and only one of them will work with your bellhousing. You definitely need to take a look at what you are buying before you lay down your money. The one you want has a normal GM bolt pattern that looks like the one on your SM318. The transmission you DON'T want looks like the one on the left side of this pic:
http://i98.photobucket.com/albums/l2...ver/NP440b.jpg
The transmission on the right has a normal GM pattern, but that one is a Muncie, not an A833.

If you want to use an NV 4500 there is no version which will bolt directly to your bellhousing. Fortunately, Advance Adapters sells a plate that will let you use a Dodge NV4500, but not the GM version.
http://www.advanceadapters.com/produ...ter-plate-kit/
You will still have to open up the center hole the same as for the A833 and also modify the driveshaft.

Ray

[melmashman]

Thanks Ray for the informative response. I have a lot to ponder.
The truck will only be used as a camper so your insight into the load limitations of other options was spot on. Thank You!
I think the NV 4500 would be great since it supplies a granny gear as well as an overdrive, but I need to check the difference in the costs since the A833 would more than likely solve my problems. I was looking at a site that had the NV 4500 and it was going for nearly $4k by itself. I was thinking that the whole job could be done for that, but perhaps I am not being realistic.
Do you know of suppliers for the A833 and the NV 4500 that might be more reasonable?
Thanks AGAIN,
Mel

[raycow]

Originally Posted by melmashman

I was looking at a site that had the NV 4500 and it was going for nearly $4k by itself. I was thinking that the whole job could be done for that, but perhaps I am not being realistic.
Do you know of suppliers for the A833 and the NV 4500 that might be more reasonable?

For $4K I would hope that NV4500 is a new one.

Seriously, I was thinking a trans for a swap like that would come from ebay, craigslist, or a salvage yard. I mean, that's where I usually look for mine. However, I can certainly understand your wanting some kind of warranty with it.

I did a quick check for rebuilt units and found the following:
http://www.drivetrain.com/parts_cata...smissions.html
http://www.heavytruckparts.net/searc...Y6&PartID=4000

Drivetrain.com is a well-known supplier that has been around for a while. The WM Cohen outfit I have never heard of before. It might be worthwhile to do a more extensive search (for price) before you commit to a supplier.

The main advantage of buying "used" rather than rebuilt is that you usually don't have to pay a core charge and you can get additional parts which don't normally come with a rebuilt. Thiis is especially important with the MY6, because you definitely need the correct shifter, mounting plate, and linkage rods for it. That particular shifter was not used on any other transmission and was never offered to the aftermarket. The shifter (or its parts) are no longer available from GM. Hurst doesn't sell parts for it either, although I understand that Hurst may offer a rebuilding sevice (not sure how they do that).

A salvage yard unit will usually carry an "out-the-door" warranty. That means it is guaranteed to be good as purchased, but not for any extended length of time after that. It is best to ask how much time you have to install and test it. On ebay or craiglslist, any warranty would be up to the individual seller.

If you want to try for a rebuilt MY6, ask if the seller can supply the shifter, even if you have to pay extra for it. This is less important on the NV4500, as the shift mechanism is located in the top cover and those will usually interchange between different models. The NV4500 stick can be swapped if you need a particular shape to clear your seat or dash.

Just as a reminder, if you want the NV4500, it has to be for a Dodge truck application in order to accommodate the thickness of the adapter plate. The input shaft on the GM version is too short to use with an adapter. Also, the Dodge unit has to be for a gas engine, not diesel (you want a 1-1/8" input spline).

On the A833, you want the GM version (often called MY6) and it must have the regular GM bolt pattern. Ask to see a picture of the front face if there is any doubt. Either trans needs to be for 2WD (not 4WD) or you will have to find some potentially expensive parts to adapt it.

Ray