front end shake
Im working on s samurai jeep, converted for 1/4 mile drag, 408w C4 with 4link suspension. The problem Im having is that at 50mph the front straight axle starts to shake bad. It starts slow and quickly starts shaking worse. Its shaking to the point that it feels like the doors and windows are gonna come off. If I slow down or hit the gas hard it stops. It also doesnt do it all the time, only sometimes. It happens more on level ground then a road thats at an angle.
I also want to mention the problem started as the alignment got closer to where its supposed to be at. When the caster,camber was way off and pulled hard I didnt have this problem.
A friend of mine watched as I drove by and said the front axle is moving horizontally alot and was surprised the front axle hasent broke off yet. Everything on the front of the car is tight. I checked all kingpin bearings, rotors, shackles, steering. I bought new tires, had them balanced twice, same thing. I checked the rear end, driveshaft, transmission mount,4 links, all are good. Someone said that I needed a stabilizer bar. so I welded on mounts, and put a bar from the axle to the frame, to eliminate the back and forth movement, went for a drive, same problem. Didnt make any difference. Then they said check the tow in-out. It was set to the spec max 1/4" toe in. He said try setting it to something ridiculous and see what happens. I set it to 1" tow in and the problem 98% went away. What would cause this? Why would excessive toe in cure a shake problem. I checked the tie rod ends by hand and they seemed ok. Can tie rod ends be bad and seem ok since I can not apply the same stress to check as seem as driving it?