[pontiacpark]

hi There, i also going to post on the GMC site as well. I am looking to buy a rebuildable core for a 4 speed hydramatic. Is there anyone out there got a core they wisah to sell at a reasonable price. I have brought stuff off of bill Hanlen in the past for my truck and im sure he can vouch for my integrity . cheers

[Bill Hanlon]

Dave is an OK guy, except I sometimes wonder if he knows which side of road to drive on.

If you are concerned about shipping outside the US, he has a buddy (in Oregon if I remember correctly) that I sent all the stuff I sold to Dave and then he forwarded to Dave.

Dave: Specifically what HM parts do you need? Don't forget that when you pull off the bellhousing and the tailshaft, most HMs are the same or at least close enough to interchange. So don't limit yourself to GMC trannies. Unfortunately (for you, not me) I just sold all my HM books.

[flat-bill]

I know very little about hydro's. But I have a '56 "dual coupling" trans. I think these are used from '56 to '60. This particular trans came off a '56 motor that I bought from Indiana Pontiacs. The motor looks really good inside and has very little cylinder top ridge. The oil that was left in the trans had a dark redish color to it. It has the "undertrans" cooler, most of the cooler lines and the adapter that bolts to the rear of the passenger side head. Also there is some of the linkage. Where is it to be shipped to? If you pay for my time to crate it, you can have it. I will be glad to see it go to someone who will use it. I know nothing about it and would consider it a core only. Maybe your luck would find it better. Let me know if you are interested. Billk

[Bill Hanlon]

Dave left out the part where he tells you his 57 GMC truck is equipped with a dual-range Hydra-Matic that GM cars quit using in 1956.

[RamAirIV28]

PM "pontirag". He has much 57 GMC hydro stuff. Lots of 57 GMC stuff in general

[stevep]

I may have a source. Is it for a V8? PM me if you have any questions.

[58cheaptin]

Is a '57 GMC trans the same as a '57 Pontiac? If so, I might be able to help you out! LMK

[Bill Hanlon]

Originally Posted by 58cheaptin

Is a '57 GMC trans the same as a '57 Pontiac? If so, I might be able to help you out! LMK

Nope. Totally different.

[U47]

Originally Posted by Bill Hanlon

Dave left out the part where he tells you his 57 GMC truck is equipped with a dual-range Hydra-Matic that GM cars quit using in 1956.

Pontiac and Oldsmobile use two Hydra-Matic's in 1956. Star Chief and Olds 98 get what Hydra-Matic Division calls Controlled Coupling Hydra-Matic along with Cadillac. This transmission is known by Pontiac as Super Hydra-Matic, by Olds as Jetaway, by Cadillac as P 315 Hydra-Matic.
1956 Pontiac 860 and 870 Models get the Dual Range Hydra-Matic along with Olds 88 and Super 88. This transmission is known by Hydra-Matic Division as "D" type. It is based on the the original Hydra-Matic of 1940 with Dual Range capabilities.

[Pontirag]

Originally Posted by U47

Pontiac and Oldsmobile use two Hydra-Matic's in 1956. Star Chief and Olds 98 get what Hydra-Matic Division calls Controlled Coupling Hydra-Matic along with Cadillac. This transmission is known by Pontiac as Super Hydra-Matic, by Olds as Jetaway, by Cadillac as P 315 Hydra-Matic.
1956 Pontiac 860 and 870 Models get the Dual Range Hydra-Matic along with Olds 88 and Super 88. This transmission is known by Hydra-Matic Division as "D" type. It is based on the the original Hydra-Matic of 1940 with Dual Range capabilities.

I think the last dual range hydro for pontiac was 55. caddy's and olds carried it over to 56 in thier low end models.

there were three distinct evolutions of the hydro between 1937 and 1956 and it was still being used by GM up through the mid 60's and by Rolls Royce through the late 60's and some sources claim up through the mid/late 70's(?)!

this does not include big truck or military applications

[Safari Larry]

Originally Posted by Pontirag

I think the last dual range hydro for pontiac was 55. caddy's and olds carried it over to 56 in thier low end models.

U47 is correct, Pontiac used the dual range in 1956 Chieftains only (not Star Chiefs). See this link and attached clipping from Pontiac Service Craftsman News, Oct 1955. Pontiac called the new transmission "Strato-Flight" and the Pontiac Master Parts Catalog refers to it as "controlled coupling". It is sometimes called "dual coupling". Some 1956 Chieftains were equipped with the Strato-Flight Hydra-matic. It appears from documentation that the Strato-Flight became available in Chieftains later in the model year.

I also believe that U47 is correct (he usually is) that Cadillac used only the new controlled coupling Hydra-matic in 1956.

[U47]

Originally Posted by Safari Larry

U47 is correct, Pontiac used the dual range in 1956 Chieftains only (not Star Chiefs). See this link and attached clipping from Pontiac Service Craftsman News, Oct 1955. Pontiac called the new transmission "Strato-Flight" and the Pontiac Master Parts Catalog refers to it as "controlled coupling". It is sometimes called "dual coupling". Some 1956 Chieftains were equipped with the Strato-Flight Hydra-matic. It appears from documentation that the Strato-Flight became available in Chieftains later in the model year.

I also believe that U47 is correct (he usually is) that Cadillac used only the new controlled coupling Hydra-matic in 1956.

Sorry Larry. I should have put StratoFlight / Super HydraMatic and I don't recall when Pontiac changed the name of the same transmission. I do know my 59 Pontiac's hydro was called Super HydraMatic.

I wonder if the 56 sales literature referred to Dual Range HydraMatic for 870-860 models.
Just a FYI, my Uncles 1956 860 Colony 2 dr wagon which was delivered late spring/early summer 1956 on special order with the 285hp dual quad 316 had a Dual range "D" type in it.

[Safari Larry]

Originally Posted by U47

Sorry Larry. I should have put StratoFlight / Super HydraMatic and I don't recall when Pontiac changed the name of the same transmission. I do know my 59 Pontiac's hydro was called Super HydraMatic.

I wonder if the 56 sales literature referred to Dual Range HydraMatic for 870-860 models.
Just a FYI, my Uncles 1956 860 Colony 2 dr wagon which was delivered late spring/early summer 1956 on special order with the 285hp dual quad 316 had a Dual range "D" type in it.

Between 1956 and 1961 there was no need to use a name that told what type of Hydra-Matic it was since there was only one, it was just a "Hydra-Matic".

Some 56 sales literature does refer to the dual-range Hydra-Matic, such as the 56 Pontiac Dealer Album and "56 Pontiac Facts Guide", page 182.

That was surely one cool wagon your uncle had!

[pontiacpark]

Thanks for the help thus far. thanks bill and steve for helping me with this. Will pm you steve. I did gewt a pm with some gmc parts that were for sale and i did reply but they were hoping to sell the parts as a lot. The trans is still working fine but i am going to rebuild the 347 v8 engine when i gwet back from POCI convention and thought it is the time to bring back a trans from your country. The right side of the road to drive on Bill my frend is as i discovered when i was last in your country the side where other cars aint coming straight toward you. ha ha

[U47]

Originally Posted by Safari Larry

Between 1957 and 1960 there was no need to use a name that told what type of Hydra-Matic it was since there was only one, it was just a "Hydra-Matic".

Some 56 sales literature does refer to the dual-range Hydra-Matic, such as the 56 Pontiac Dealer Album and "56 Pontiac Facts Guide", page 182.

That was surely one cool wagon your uncle had!

Yes, and from 1961- 64 full sized Pontiac's automatic's were referred to as HydraMatic even though Pontiac was using Super HydraMatic and Roto HydraMatic. It's only specific when it comes to service manuals and shop bulletins.

[pontiacpark]

Is there a serial number on the transmission housing that identifies it as the correct one. If so where is it located.

[Bill Hanlon]

Dual range Hydra-Matics had a label held on by two rivets in one of two places that I know of. One was on the passenger's side (right side to you Kiwis) of the case, a couple of inches above the bottom pan rail about centered front to back. The other (where all the GMC truck HMs I've ever seen had theirs) was on a slanted surface, just below the side cover, on the rear of the transmission case to the left of the tailshaft.

[Safari Larry]

See attached for location of the ID plate on 55-56 (and some years earlier?) Pontiac dual-range transmission (from 1956 Hydra-Matic Manual - Part II Dual Range). Bill, the photo you show is not the "slant pan" dual-range Hydra-Matic that I'm used to seeing?

[RamAirIV28]

some hydro's the data plate is located on the rear of the main housing next to the tail shaft housing on the driver side.
on older ones its located on the side of the main housing.

the color of the tag will tell you information about the tranny origin But be carefull what kind of degreaser you use to clean the tranny as it can alter the color or remove it. Oven cleaner works well to clean them but can alter the color or even remove it.

also the alpha numeric serial number stamped on the tag will tell you information, I think the year of manufacture and the corporation and a serial number

[Bill Hanlon]

Originally Posted by Safari Larry

Bill, the photo you show is not the "slant pan" dual-range Hydra-Matic that I'm used to seeing?

Slant pan was 55-56 Pontiac and 54 (I think) to 56 Olds. The picture I used was taken from the "On the car adjustments" manual that you loaded on your web site. More generic.