automatic transmission woes

[Dirttrack510]

ok, so here's the deal... I bought this 510 about a year ago with half a motor in it. I just did the engine swap & put in an L18. It's running great. Problem is the transmission is slipping and it sounds like it's the bands that are slipping. A friend told me that on some old cars you could adjust & tighten the bands. Can i adjust these as well? I have the Muncie style tranny withe the oil cooler lines that go to my radiator and the column shifter. My tranny is a 1971 model year if that helps. Thanks for any help.

[MikeRL411]

ok, so here's the deal... I bought this 510 about a year ago with half a motor in it. I just did the engine swap & put in an L18. It's running great. Problem is the transmission is slipping and it sounds like it's the bands that are slipping. A friend told me that on some old cars you could adjust & tighten the bands. Can i adjust these as well? I have the Muncie style tranny withe the oil cooler lines that go to my radiator and the column shifter. My tranny is a 1971 model year if that helps. Thanks for any help.

You have the American. Muncie< BW transmission. The adjustments are made to the transmissiopn control unit requiring you to tap into the vacuum line and use a tachometer to properly adjust. The proceedure is best left to a professional because to quote the adjust instructions which require reving the engine to 1200 RPM " CAUTION. Do not continue this test for more than 10 seconds or transmission overheating and damage will result."

 

Yes, you can. No, you should not try it.

[datzenmike]

The 3N71B Nissan/JATCO auto was introduced in April /71. Would yours be made on or after that date?

 

All auto oil pans are square (rounded corners) in shape except the 3N71B which has the driver's side indented.

 

Automatics are notorious for being difficult to diagnose for 'slippage' as they are infinitely variable between 1:1 and 2:1 in every gear due to the torque converter. All automatics are fluid drive and when throttle is added the motor will rev up slightly against the liquid. This is the same as an airplane propeller revving up and slowly the plane gathers speed and rolls down the runway.

 

If on the other hand you are familiar with your car's performance and there is a sudden change that would be different. I would suggest changing your fluid if it is old (over 50K miles) or has ever been used for towing, (very bad) or has ever been overheated, or the color is anything but clear, see through bright RED in color.