68 C6 transmission differences

[Dan Szwarc]

Unibody Continentals 66-69 only.

[frasern]

It was similar on PCA transmissions, but only 2 elongated bearings, I don't know if it was used in late '50s.

[TonyC]

I may be wrong, but I don't think they were. In '61 there were some articles about the changes they made, and those needle bearings were one of the showcased changes they emphasized. Plus, the transmissions used in '58–'60 were different from the ones in '61–5; the innards may have been similar, but the casing was different, as was the arrangement of the innards in the different casing. That's what makes the PCAs such an exclusive headache to deal with.

On the other hand, no other production car used that slip-yoke design to my knowledge, which can fuel questions about how much more effective they were over typical splined slip yokes. Some, however, did adopt the double-cardan joints.

Yeah, that is a crazy design, but I like it. It wasn't without issues, I admit, but those issues were not really intrinsic to the design. They stemmed from mechanics who were not familiar with them, and tended to be careless with the drive shafts if they ever had to take them off for other services or repairs. When they dropped the shaft on the floor, those bearings tended to fall off their key mounts and out the yoke, and they wouldn't think of putting them back in. When that happened, even worse problems would result; just one missing bearing would cause chain-reaction destruction of the remaining ones...then, of course, there's the destruction of the output shaft on top of that. I know that common sense would dictate an inspection and reinstall in such a case, but common sense wasn't all that common for many mechanics back then.

I remember Mark II Enterprises sold some aftermarket fillers made of brass to replace the OE bearings (apparently they still do). They were just one-piece brass blocks, no rolling needles or anything. I never thought that to be a good idea; I can imagine the friction would wear the brass down, even with fluid running all around them, sending bits into the transmission, causing eventual all-around destruction. I prefer to stick with the proper ones, which were designed to mitigate friction damage. Despite M2E's rather cocky claim about their superiority to the original rollers and forever endurance, I just have to think otherwise.

---Tony

[Dan Szwarc]

Simple quick drive shaft needle bearing question

A post from 2017. With Pics of the needle bearings.

[Mcdizzle83]

Thank you for all the response guys. I sent the information over to my mechanic. Napa has them in stock for $15 and fit perfect.

Beyond grateful for the knowledge base y'all possess.