Hello

I had my 1964 T-Birds Cruise-O-Matic rebuilt. The reverse slipped and it leaked oil. Now the rebuild is ready and I have a couple of hundred miles on it. At first all worked fine. But after a while it started to keep slight grinding noise on first gear. Not all the time. Just sometimes when I slow down and tranny changes to first. Then when accelerating it keeps this grinding/rattling/gurgling sound. It stops if I lift the pedal and push again. It also stops when tranny changes to second.

When this first time happened I checked the oil level. The dipstick did not even touch the oil. I filled it up. Tranny still sometimes keeps this noise. Yesterday I checked the oil level again. It had gone down a bit. I filled it up.

I asked the rebuilder if he knew what this is (has rebuilt transmissions for over 30 years as a professional). He suggested that it could be the vacuum diaphgram that is leaking in to the intake. I checked the vacuum line and it's clean. No oil there. The tranny isn't leaking anywhere. At least my garage floor is clean. Not a drip of oil there. The cooling water is also clean.

I asked for a second opinion from my neighbor that is a former Ford mechanic and knows a lot of these cars. He suggested that when the rebuilder has filled the tranny up with oil, the turbine has not filled up completely. It's now slowly filling up. Could this be the answer? Is the grinding/rattling/gurgling sound air somewhere in the oil passages/turbine?

I use Gulf ATF Type F.

Mika, Finland

That sounds like planetary whine.
Is it very noisy in manual Low position?

I have not tried on Low, must check. I'm pretty sure that when I try to get that sound out of there it does not do it. As I told it happens only sometimes. There can be a couple of days when it does not appear at all. And on D it's not very noisy at all. Just slight grinding sound.

Planetary whine, is it serious? Waiting for big damage?? Well, the rebuilder gave the tranny a 10 years warranty

Mika

Tried and tried with Low. No grinding, no. Just like I guessed. Checked the vacuum modulator again and the cooling water. No oil there. Well I just have to follow. Contacted the rebuilder again. Warranty still stands.

Mika

Hello again

Yesterday I checked the fluid level and now it's OK. No loss of fluid.

But the grinding sound still exists. The car is going back to the shop for recheck in couple of weeks.

But one more problem is still there. It had this problem already before the rebuild. Right after the rebuild it was away but now it's back. When slowing down, the transmission is shifting down to first, there is a loud clunk/bang. I asked this from the rebuilder and he said these downshift clunks may come from the rear axle differential or drive shaft u-joints.

Anyone else had these downshift clunks? Did you find the reason?

I want to know where that oil is going.
Have you checked the radiator for oil in it?
I am betting that the cooler is leaking tranny fluid into the cooler.

Hi Paul

I have checked the cooling water. It's clean.