The trans was locking out fine before. The only thing I changed was I added a drain plug in the pan, put new champion 3 row aluminum radiator in. New braided 6 an lines from tranny to external cooler mounted in front of rad. I did put new filter on while the pan was down. I am stumped. The car shifted smooth before. Now it revs really high rpm before shifting to second third and hardly will go into OD. Now the drain plug was really close to something on the bottom of the trans so I had to shave off the bolt I welded in down to about an eighth inch and the pan fit on good but was real close . I'm wondering if there is something being restricted? When I put my foot on brake pedal I can't get engine rpm to go up for lockout. I don't know wth is going on here. I will add a pic of drain plug location. It should have been another inch to the left for a better spot but even so I didn't think there were any moving parts at this spot but there is something that hangs real low right there.

 

DO NOT drive it. Check to see if you are getting fluid from the radiator to the transmission. Disconnect the top line at the transmission and place it in a clean container and see if you are getting a good flow of fluid. You only need to do this for a few seconds. I have seen this before, and the transmission was gone in just a few miles due to no fluid getting to the lubrication circuit. The aluminum radiator was the culprit in both cases.

 

Hello Pro built that is good to know. You are saying that the transmission cooler in the radiator is defective right out of the box?

 

Yes, I have seen this twice with my customers over the years. It "wasted" the gear train, as no fluid was going to the lubrication circuit. I am not saying that this is happening in your case, but just make sure that it isn't by doing what I stated above.