I've recently aquired a 68 mustang. Ran and drove perfect. I had to replace the flexplate, did so and got it back together. Took it for a test drive, it shakes horribly. Only shakes while moving. Any ideas? It even does it at super low speeds, so i feel like it isn't the driveshaft. I can feel it in the steering wheel and the accelerator, and it vibrated pretty hard. I came here because i also have a maverick and in my opinion this is the most useful forum on the net. Thanks!
Only while moving, that's why I didn't think its the flexplate....its the original engine I just got the one it called for at autozone....its weird I can feel it so heavily in the pedal
Why did you replace the flex plate? Did you get the converter seated properly in the front pump of the transmission? Does the car shake when you are in Park or Neutral and rev the motor?
If it's the flex plate, you should be able to feel it even when the car is sitting still...is this the case? If not, I'd check for a broken belt in a tire before I pulled it apart again...
Brand new tires, im pretty sure its something else. I guess I got the conveyed right, the teanny bolted up fine. Is there a specific waybit should be turned? The converter that is
I'd still take a good, long look at the tires and make sure it isn't them. Anythime I've been around an out of balance situation...it was OBVIOUS at idle. With that being said...it doesn't mean yours isn't...it just wouldn't be my first inclination if it only does it while moving. I'd jack it up and check all the suspension parts just to be sure before I dropped the xmsn again...just my 2 cents. Hope you find it...stuff like that is what drives you completely nuts until you figure it out!
Haha I sure hope so! It's so inconsistent too. Doesn't vibrate the same way at the same time always. It does kinda feel like a wheels falling off, but it also surges in the pedal. I thought maybe engine mounts are bad from having the weight of the engine sitting on them with no tranny for a week, but they don't look obviously messed up in anyway....and it doesn't shake at idle
Check tires for a shifted belt/out of balance. As long as your certain you installed the converter correctly...Check the front U-joint on the drive shaft. It should have no side to side/up down or forward/reverse movement against any of its normal axis of operation. If it does...you found your problem. Is the drive shaft rear joint sitting properly in the differential yoke??? (it should be centered in the yoke)Are the U bolts/clamps secure??? If this all looks good...remove the driveshaft and see if the front joint moves smoothly through is axis. If its very tight or feels crunchy and or binds up any where along is rotatoinal axis...Its bad. This will cause your vibration. Not saying its the cause but its the most obvious after a shifted belt/unbalanced tire/wheel...Good luck!!!
I'll check it out, but the car was my daily driver with brand new tires 2 weeks ago so it seems unlikely
Not unusual for a wheel to spit out a wheel weight...I have seen new tires spit out a belt after a few weeks also...Usually cheap price club tires like you get at walmart/sams club etc...
I tend to lean toward a problem related to the recent change. A tire problem at the same time is possible, but the coincidence is a bit much for me. My first impression was wrong flexplate ... early motors use a 28 oz imbalance, late uses 50 oz. If it is a late motor in an early car, easy to mistake what is needed. If it isn't shaking violently at idle, it kind of rules that out though. When you reconnected the driveshaft, did you put it back together in exactly the same positions on the yokes that it started at? Sometimes turning a yoke 180 degrees will give you a shake. Other thought .... too tight/too loose on the u-bolts for the driveshaft. Are they torqued to spec? Still ... my experience with a used-up set of u-joints meant a bad shake at 40-50 mph, OK above or below that.
You may have gotten the wrong one. Most of today's counter help only can read the computer and get the parts it tells them to. Unless you get a good counter person OR a real mechanic, 9 times out of 10 they only look at the first one they come to or the price of the part without checking to see if there are different parts listed for the same application. You also might have gotten a slightly out of balance part. It's not unheard of to get a bad part new in the box in today's mass produced for the cheapest price possible parts market. One last thing to check is if it is installed properly. If it is out of line (there should be an alignment pin if I'm remembering right) it could be out of balance OR if the bolts were just slammed in one at a time instead of using the correct sequence, or if it was over tightened, it could physically warp causing your vibration. Hope this helps, -Scott H.
