Packard Forum Index » Modification Discussion

I have a 53 patrician. Has anyone attempted to use rear end gears or an LSD from a different vehicle in the packard axle to change the ratio or add limited slip? Looking at an overdrive trans but dont need to cruise at 90 mph.

Thanks
John R.

I don't think you need to consider other makes of vehicles unless you absolutely want limited slip. With Ultramatic the 3.54 rear axle was usually supplied and it should let you cruise reasonably effortlessly at 65-70 mph all day long. And if you want something taller, Packard offered a 3.23 ratio as well for the '53 Patrician. So if you go with an overdrive transmission, there would seem to be no reason to change the rear axle gearing.

Until the experts show up...
It's pretty unlikely that there is a brand X carrier that will fit the Packard Diff, certainly there are varying ratios available though. If you need a Posi, find something that fits & weld perches on it.
There is the '56 Dana assembly that I believe uses standard Dana 60 guts. If that is the case, then the sky is the limit! Just weld some perches on.

Packard also built their own rear ends in 53 so I doubt any LSD would be able to mount in the housing. I know changing the entire rear has been done by a few but don't believe any of them were simple drop ins and able to fit without some welding and mods to provide a different mounting.

Didn't Packard offer a limited slip differential with its 1954 models? I know they were the first to offer tubless tires in production models this year and thought they had the LSD too. If so, a LSD from a '54 should bolt right in with no modifications. If not, how about a '55 or '56 unit from a conventional suspension car? One of these units may require some mods to make it fit.

I could be wrong but thought the LSD that became available with the switch to the Dana rear end in 56 was the first offering. Packard called it Twin Traction and I believe it also became available on some Stude products.

Swapping a 56 rear axle with TT seems hard to find and still no gearing choices?
John

There were several ratio choices for the regular Dana axles in 56 and according to bulletin 56T-8 5 ratios were available with the TT axle. 4 on one assy and the highest -- 4.09 -- required a completely different assy. TT was a later addition and there is no specific mention in the earlier printed versions of parts and service literature. Other than the bulletin and some theory of how it operates in the April 56 service counselor there is no real nitty gritty of how to repair one other than a statement that a TT rear end was serviced in the same way as regular axles. If there was a problem with the TT part the unit was to be replaced as an assy because there were no detail replacement parts available.

From what I have read in other publications the unit Packard used was a very early version of the LSD. I believe Dana changed the clutch engagement from a single tapered contact surface around the circumferance of the clutch to multiple clutch discs with a much greater contact surface in the next LSD axles to make the clutch locking more positive and able to hold more torque. If that is the case I am not sure I would want the early Packard version even if it were easily found and could be mounted without difficulty.

OK, I am intrigued--why LSD? Are you planning to use this car regularly in the snow? For occasional use in the snow, I would just recommend chains.

The usual 3.54 gears will have you turning 2500 rpm at 60, 2300 if you have 3.23 gears.

A 56 axle will bolt in easily except for changing the spring perches. Then you can get a 3.07 gearset which will yield about 2100 rpm. This is all a lot of work to save 400 rpm. Perhaps I don't grasp what you are hoping to achieve.

The interest in an LSD was for traction but only secondary. But my real interest was higher numerical gears as part of changing the trans to a modern automatic overdrive unit. Maybe a 0.70 overdrive 4L65e or other.

John R.