Was automatic transmission offered in our trucks?
 

Members,
I am converting my '64 wideside SM420 to an 700R4. Is there a floor tunnel hump that's available that will unbolt from the floor and exchange? Other people have said I may need the high hump for the 700R4??
I suppose I can cut and adjust as needed esepcially if I install a floor shift.
Thanks for the info...Tom

Re: Was automatic transmission offered in our trucks?
 

My '63 Suburban came from the factory with a Pow_R_Flo 2 speed automatic, AKA Powerglide.

Re: Was automatic transmission offered in our trucks?
 

ItalOso, you would need the so called high hump cover along with the spot welded cowl piece in front of it. Mine came from a salvage yard, but I think they are being reproduced. Not sure if the spot welded piece is repopped.

Re: Was automatic transmission offered in our trucks?
 

Found this on a FB group for C10's, might work for you -

https://www.facebook.com/groups/1690717247836638/

Re: Was automatic transmission offered in our trucks?
 

I'm reading on another forum that it would fit with very little work.

http://www.67-72chevytrucks.com/vboa...+hump+comparic

Re: Was automatic transmission offered in our trucks?
 

Thanks Members for your answers and points of reference. For me, the interior space, as in other posts I have sent, having a lower hump would be excellent as I wear a size 16 shoe. Even if I was able to shave off 2-3" or round the floor board to fit the transmission a little better, that would be great. We'll find out after we pull the SM-420 and see what happens next.

Re: Was automatic transmission offered in our trucks?
 

I converted to a 700R4 years ago, my truck used to have a 4 speed manual transmission. I just slide the transmission as far back as I could before it hit the firewall/undercarriage, left clearance, then bolted the transmission cross member into the new location and made sure the new drive line was the correct length. I do have a 350 Chivy motor in it, if that makes a difference. However, i am happy to report I have procured a nicely running 305E that I plan to put in the truck and get rid of the 350.

John

Re: Was automatic transmission offered in our trucks?
 

Yes, they were as an option. However, in order to install an automatic to a GMC V6, you either need an adapter, flywheel, and starter from another V6 that had either a Powerglide or a th-400, (found either on this group or e-bay) or order a custom built kit. Jolly's pages still have the info on this. The GMC V6 has a bolt pattern that is unique-nothing else fits!!! I hope I have been of some assistance in your quest.

Re: Was automatic transmission offered in our trucks?
 

Another consideration is the engine mounts. V-6's with manual transmissions use 4 engine mounts, 2 at the side of the block towards the front and 2 off the bell housing. There is no transmission mount. The bell housing mounts are typical GM medium duty truck mounts with upper and lower cushions. These are important because they take the (considerable) torque force of the engine, the small front mounts primarily just hold the weight of the engine. V-6's originally equipped with automatic transmissions had much stronger front mounts to take the torque and also had a rear cross member and mount supporting the transmission. No mounts off the bell housing. So, if you are converting a V-6 truck from a manual to automatic transmission you may want to figure out a way to strengthen the front engine mounts.

Re: Was automatic transmission offered in our trucks?
 

Bob, there was a thread a number of years ago in which the transmission mounts for a Jeep from Energy Suspensions (p/n 3.1108) would work. It looks like a viable replacement for the O.E.M. mounts that are no longer being made. They are much stiffer than the original mounts.