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Hi All,

Have a problem that has been creeping in and getting bigger since mid-to-late-summer. It started with a mild "Shudder" (For lack of a better word) on acceleration at lower speeds with the transmission in H. The problem has been consistently getting worse each time I take her out. I took the car for about a 120 mile trip about a month ago and on the way back the shuddering got really bad whenever I tried to accelerate and decelerate. I also started to get a squeak from the rear end and differential fluid is leaking from both back wheels (On the inner side). I hadn't started the car for about a month, so went for a quick trip around the block today and another new symptom arose. The was a chirp that appeared to be coming from the ultramatic. (Stuck my head out of the window and definitely was coming from the front.) The chirp was related to wheel speed. and only happened when going 5-10 mph. and only happened when the shuddering was present.

I'm guessing that the rear bearings are shot and the Universal joint may need attention, but the chirping transmission really has me puzzled.

This one is a bit over my level and I called the local shop, but they said they have to get at least on car out before they had room for me an I should call back in a week. Until then just want to see what you guys think.

Considering just one of several possibilities Dave . . . Seems likely you'll have to replace your oil seals in the rear axle housings as that would account for the leaking diff oil (- if you are certain it is diff oil, and not brake fluid -??). Rear wheel bearings might be OK, with just the seals worn out.

It's possible that the 'shudder' could be related to these leaks. The rear brake shoe material can expand and grab when it gets soaked by either oil or brake fluid, and the expanded shoes could be grabbing the drum causing a mild shudder, which would be worse at low speed. If the brake shoes have been affected by oil you'll need to replace them.

The idea is to isolate one problem, fix that, then maybe the chirping will also go. Dunno much about Ultramatic problems, however it's possible that inconsistent/varying load on the Ultramatic might be causing the noise. There are a good many people on this forum that will have some additionalideas.

is there a fluid puddle under where the car was parked?
a pint of transmission fluid covers 7 square feet ,the fluid is red dyed .The ultramatic can have a slow leak from the pan gasket, and from the bushing where the shift selector rod goes in to the case where theres a bushing that can wear out .low fluid levels can cause a chirpy noise .
to check the fluid level ,,the easiest way is up on a lift... if you dont have a lift you can do it from the iside of the car; driver side pull back the back edge of the carpet or mat theres two holes ;the one on the top of the hump in the midline is the filler hole ,and the one on the driver side of the hump is over the dipstick .its a bit hard to reach

Had a shudder on hard acceleration on my 51 but didn't seem to do the same on deceleration. Turned out to be a worn trunnion universal. The housing was worn quite badly. Rear end oil leaks are just that. Check for leaking axel seals and for leaky brake cylinders. If the diff fluid has leaked out due to bad axel seals the gears will be damaged, and hence, make noise. Check the fluid level. Theres more to it but that is a place to start.

In addition to a worn ball & trunnion front joint which is a good possibility, other possibilities for chatter on acceleration are dragging or misadjusted low and/or reverse transmission bands, and possibly worn or distorted high range clutch plates.