TH350 rear seal
 

ok simple question.... I have this Timken 5200 rear seal, I've replaced many seals but this is the first time I've seen one come with this bushing. Before I get under the car to replace it I'd like to know where the bushing goes.

It's the driveshaft yoke support bushing, this should be changed out also as the leaking at the seal is more often then not caused in large part by a loose support bushing letting the yoke move around .

Note also that the welds at the inner side of the yoke have been know to rot away some and then that pin hole leaks fluid also!

The yoke moving around enough also makes the driveshaft act like it's out of balance and this movement just eats up a new seal.

The bushing is a press-fit into the tailhousing. There is a special puller tool to remove the old bushing (works on Muncie 4 speeds too--same bushing) that is needed to do the job. Put the new bushing in the freezer for an hour, and simply drive it in square with a block of wood or a socket that fits well. Without the special puller to get the old bushing out, it's not really do-able in car with the tailhousing attached to the trans. A ten minute job with the right tools, and yes, if the seal is leaking, the bushing is likely worn. Check the yoke for wear as well with a straight edge. They tend to wear like a saddle with a lot of miles. BTDT.....

Take the extra 5 minutes to remove the tail housing and replace the bushing and seal.

No special tools are needed to R & R the bushing. Just grind a slight angle on the end of a large flat tipped tapered punch. Locate the "seam" on the bushing, catch the edge of it with the punch and hit it with a hammer to split the bushing. A couple of good hits and it will basically just fall out of the housing. If you hit the aluminum bore the bushing sets in no big deal just relieve it with a round file of pocket knife.

The seal can be removed in similar fashion with the same punch, catch the edge in 2 or 3 places and drive it inboard and it will fall right out of the housing.

If you don't have a bushing driver drive the new bushing in with a large socket turned upside down so the flat surface drives the bushing in flush. The seal is driven in flush in similar fashion, use some red Loctite to retain it and the same with the bushing, they aren't difficult or fussy to R & R.......Cliff

Who sells this bushing. Sounds like a good idea to change.

I don't consider it an option with seal replacement. You want minimum movement of the driveshaft which improves seal life and reduces any potential vibration due to a loose fit between the driveshaft yoke and transmission.

For the TH400's there is a long bushing available and recommended vs the shorter version......Cliff

I never thought about that, is there room for 2 of the shorter support bushings?

No room for two and they don't make a longer one like they do for the TH400, at least that I'm aware of.......