Packard Forum Index » V-8 (1955-56)

Quote:
"Also, the car sometimes works to get into direct drive. "

Not sure what that means. Does that mean a groaning sound, or the engine suddely 'flares' (races to hi rpm mommentarily) or does it mean that it hangs out in converter drive along time before shifting to DD????

In any of those cases changing the fluid not likely to help except MAYBE the groan.

Quote:
"My modern car is rated life of the car for transmission ..."

Just out of curisoity SPECIFICALY what IS the 'life of the car"???? Answer is either in number of years and/or number of miles. Would there be some other way to measure it??? I really have no idea.

It chatters going into high---sometimes.

A poster in the previous thread on this subject noted that switching removed similar chatter in his trans.......

I'm just fascinated that so many of you think trans fluid is essentially permanent. My impression, not based on any known scientific proof, is that the fluid deteriorates over time and use.

As previously noted, clues in other areas when I got the car indicated a lack of quality on schedule lubrication. Hence the thought that the trans fluid was questionable.

This thread is why internet info gives people gray hair. So many opinions sincerely shared...but they disagree.

owen, and others, i found a great product, RM25, for coolant, cleans and protects.

I had a chemist look it up, specs. he said it take the oxygen out the coolant so rust can't form.

rik

Can you be more specific about RM25? Google yields dozens of RM25s of all sorts except....

"Life of the car" for transmission fluid means there is no required service interval. Just like sealed suspension parts and differential oil. The only time the fluid requires replacement is when the transmission is replaced.

But the manual for my modern car does list a service interval for towing and severe driving with high oil temperatues as per mountainous regions.

One thing about transmission oil is the additive "packages" keep changing. If an old transmission has good oil the clutches have been soaking in that oil.

I found with a couple of cases with cars taken out of long term storage that changing the oil in the transmission was not the thing to do. These were manual transmissions and they just didn't shift as well no matter what I tried. Even the exact oil specified by the original manual. Maybe the transmission and oil were both shot, but given new parts are not available in those cases fooling with the oil was a mistake.

Getting back on the original subject if an Ultramatic is having an intermittent direct drive lockup problem I think that switching to Type F might be the way to go. Supposedly Type F will run higher pressures than Dexron. Packard did specify friction modifiers in a 1956 TSB, but I think that was to address synchronous shift problems in Drive range.

Eventually these transmissions are going to need soft part modifications to compensate for worn surfaces the same way as a modern car.

sorry,,,left off letter......RMI-25,,made by Radiator Masters

part no. 00825,,,

this is GREAT STUFF,,,,google it....


rik

On the subject of fluid condition let me add this note pertaining to Mopar ATF+4

a) The red fluid color is from dye to distinguish it from other oils
b) Mopar ATF+4 and Mopar Power Steering Oil + 4 are the same product and interchangible
c) The color of the fluid may change to brown with use and color is not an indication of fluid condition
d) The odor of the fluid may change with use and is not an indication of the condition of the fluid

These are actual service guidelines from Chrysler. So aside from listed maintenance intervals the only recommendation to replace the fluid in a Chrysler is when the transmission is changed or if there are symptoms.

Now of course, modern transmissions have good filters. The Ultramatic doesn't and would benefit from an add on. But, once the car is parked for a week there is a alot of settlement which is probably why they seem more reliable today than when they were being driven all the time. I doubt that "modern fluids" have much to do with it.

Small Question on the top of this...has anyone found a transmission filter that is interchangeable with the ultramatic?

I've always wondered if putting some kind of canister filter in one of the lines going to the cooler would be effective. I have 3 coolers on mine and don't use the in-radiator one. (one long aluminum tube cooler on the frame, and two stacked plate ones on the radiator.) I've often thought about putting a canister filter in there somewhere, maybe hidden in the front area in front of the radiator where the coolers are, or bolted to the frame where the one cooler is. My worry though is that it would affect pressure someway and that might cause issues or damage to the transmission.