View Full Version : Cruise-O-Matic shifting
10-27-2014, 09:55 PM
I am trying to figure out if Im having shifting issues. My shift lever has P, R, N, D2, D1, L. can some one explain the difference with the D2, D1, L. The reason i am asking is that I am only feeling one shift when I drive off in D2. Maybe I should start off from D1?
Thanks 61 Thunderbird 390 Cruise a Matic.
10-27-2014, 10:43 PM
You should start in D1. That gives you the normal drive range from first gear, to second gear, to third gear. D2 starts in second gear. L is first gear only.
10-28-2014, 08:24 AM
L can also be used to downshift from 3rd to 2nd at higher speeds. As the car slows down further it will then downshift into first and stay there.
10-28-2014, 08:51 AM
Randy agree with John always start out in D1.
10-28-2014, 10:48 AM
Thank you John. I think i have been starting off in D2 all this time thinking it was the correct drive off possession. Perhaps starting off in D1 it will feel a bit quicker from the get go and not as sluggish.
10-28-2014, 10:57 AM
interesting info but sounds scary to attempt. Imagining going down the road in 3rd and then manually shifting to L? Not sure I fully understand.
10-28-2014, 11:18 AM
Here's a link that explains how the gear selection works. You can find this info in the Technical Resource Library.
10-29-2014, 08:05 AM
Good read John. I assume the little dot big dot on my 64 corresponds to D2 D1.
10-29-2014, 10:03 AM
Great information Sir! Exactly what I wanted to know. Thank you!
10-30-2014, 09:26 AM
So lastnight I took the 61 tbird out for a drive after putting new modulator on the trany, replacing vacuum hoses and adjusting the shift linkage (I hope correctly) and started off in D1 this time. The Tbird seems stronger as I started off and it did shift into 2nd yet not so smoothly and did not shift into 3rd. Any thoughts I might recheck/do for not shifting smoothly and to shift into 3rd?
10-30-2014, 09:57 AM
Has the car been sitting for a long period of time. If it has there could be sludge buildup in the pan and filter. If you haven't done so I would remove the pan and clean it out, clean the filter (it's metal so you don't need to replace it) and put in fresh Type F transmission fluid.
10-31-2014, 05:35 PM
thanks for the tip. But I have been driving it here and there through out the summer and before. I think I just need to recheck the linkage adjustment again.
10-31-2014, 05:49 PM
The linkage only affects what gear you start out in. Shifting from gear to gear has nothing to do with the linkage. That's all internal.
11-03-2014, 06:06 PM
Ok so I think I got in a hurry when reconnecting the vacuum tube back to the modulator and didn't get it on like I thought. After rechecking and
getting it connected properly the Cruise O Matic seems to be shifting great. Thanks for all your help.
11-03-2014, 08:08 PM
Yep. That would do it.
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