Re: Checking transmission fluid

Posted by Owen_Dyneto On 2011/9/21 10:37:29

It's not that you need to update your transmission to take new bushings, it's that the bushings wear and the clearances (leakage at bushings) establishes the hydraulic pressures, so bushing and/or shaft wear = pressure loss = ultimate transmission failure. A rebuild with soft parts only (linings, gaskets, etc) without paying attention to bushings & shaft wear is just an exercise in wasting time & money.

I'm not aware of any machining required to fit new bushings, but Ross should be able to offer definitive comment. It is possible, especially as concerns the input shaft, that if the shaft is worn or scored, simply replacing the bushing won't reestablish the needed pressures and certainly won't do much for the life of the new bushing either. Solution is a "rebuilt" shaft, plated up and ground back to standard dimensions. I know Ross has done this many times.

As far as the under-floorboard dipstick, I can find myself sort of agreeing with Fred. The car requires a chassis grease job every 1000 miles so it's going to most likely be on a lift anyway to grease, check differential oil, check brake lines, universals, etc. So since it's on the lift that often, checking the Ultramatic shouldn't be any real additional burden. And if it leaks so profusely that it can't go 1000 miles without needing fluid, that really should be attended to promptly. Certainly adding the underhood dipstick was an improvement and consistent with what other manufacturers were doing but when you consider the under-floor filler and dipstick you should also consider the date of the engineering and the engineering practice at the time.

Was the Ultramatic a work-in-progress? Name an automatic transmission that wasn't constantly upgraded and changed.