mhartley

I recently acquired a 55 olds rocket 88 with a hydra-matic, and the PO took out the tranny cooling lines and looped a short hose from the output back into the input on the tranny, leaving the tranny with no cooling. I looked at the radiator but I can't find any evidence that the radiator was ever set up to accept the tranny cooling lines. My questions are:

1. Is it okay to run an aftermarket tranny cooler with no radiator cooling (easiest fix IMHO).
2. In case my radiatory is set up to accept the cooling lines and I am just blind, where should I be looking on the radiator?
3. Does anyone have pics or knowledge as to where the cooling lines should run from the tranny to the front of the car?
4. Should I use hard lines the whole way or use a short piece of flexible hose at the tranny to allow for the movement of the tranny?
5. Is 5/16 line the right size for both hard and flexible lines?

Thanks in advance for your help!

rocketraider

I expect the radiator was replaced with one for a stick car, which would not have had provision for the cooler lines. They will be in the bottom tank if it has them.

Back then Olds used a combination of hard lines and rubber lines for transmission cooling. The radiator end had a rubber section and brass nipples angled to route the rubber hose toward the passenger side of the car, where they connected to the hard lines.

You should be fine with an aftermarket cooler mounted in front of the radiator. You just won't be able to maintain the ideal 180 degree transmission oil temperature as you would if it had a radiator tank cooler.

mhartley

Thanks Rocketraider. Do you know if the hardlines should hook directly to the tranny or if there should be a hose between the tranny and hard lines?

Tedd Thompson

There are no cooler lines on a stock 55 transmission.Are you sure it's a stock transmission? I can't even find a place on the case that would adapt for cooler lines...Tedd

citcapp

could it be a 371 and hydro transplant from a 57?

Tedd Thompson

mhartly, does your transmission gear selector have a park designation or is reverse park with the key off? If you have a park your transmission has been changed to a later transmission. This could be why it's plumbed differently than any 55 I have been around. I don't think late 56 models had coolers either.You might want to check it out before you start adding parts that you may or may not need. Tedd

mhartley

Tedd, My parking indicator on the dash does not have a "P", but the letters do not match up either. In actual use, far left is Park and far right is reverse, so based on what you are saying I must have a later tranny. It is definitely a 4 speed because I can hear it shift, and it also shifts hard from 1st to 2nd like a typical hydrmatic. Any idea if the later version of hydramatic tranny needs a cooler? It is not a big deal to add one, but if I don't need it I would rather not do the work. Attached are two pictures of the approx 12 inch hose that loops where I think the cooler lines are supposed to be attached.

Citcapp, is there any easy way to tell which motor and tranny I have?

Tedd Thompson

mahartley, to help ID your engine without opening anything up check your heads. Top of the left center exhaust port of each head should be marked with a number- 58 371 is # 16 or #17 1956 324 is # 10 and 1955 324 is # 9. This won't help with your tranny ID but may give you a better idea of whats been changed on your car....Tedd

euroman1

mahartly,my tranny has the same cooling line outlet like yours shown in the pics. mine is a '56 tranny and this fits according to my olds parts dealer only behind a '56 324 engine because it is a one year only.the yokes are different and the balancing.the '56 has a slip in yoke and the '55 a bolt in or how ever it is called.

mhartley

Euroman, where do the hoses go on your tranny? I will see if I can id mine using the info from Tedd and the yoke. Thank you all for your input.

euroman1

mhartley,
they run from the outlet along the passenger side framerail to the radiator.i have hoses at the tranny outlet,maybe 4in long and solid lines going into the rad.the tranny in the pics is a '56,behind the gearselector is the id tag.

mhartley

My tranny matches Euroman1's picture and my heads have a "10" on them, so it appears I have 1956 engine and tranny in my '55. Looks like I will be installing a tranny cooler next weekend. Thanks for your help guys!