Mystery vibration at 25 mph can't be diagnosed. It's not the front end!

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1) It has yet to be verified whether this is an engine speed shudder, a driveline speed shudder, or even a wheel speed shudder. Since We here on the forum have almost
no way of experiencing this 1st hand, slantsixdan gave the OP links to literature which should help Him figure this out.
2)If it is engine speed it wouldn't be "only at 25", and engine load/strain increases in higher gears, but the OP needs to verify this. I have already stated how.
3)If it is driveline related it will only increase with vehicle speed, regardless of the eng. RPM...the only exception being the torque converter/input shaft-drum assy.
4)It is very common for a tire with a failing belt to tug or deform at precisely the 20-25mph range, on the front it tugs on the steering wheel, and in fact just happened
to Me on My 'rolla. I was hoping that set would last Me 'till I mounted the snows, but nope, one day moving out.....tug tug tug..... so it's not impossible for a belt to
show it's given up the ghost under torque by causing the car to shudder.
5)Frequency frequency frequency, what is it in relation to the above systems................................
 
Killer6, I have brand new Kelley tires on the Crager Mags. Probably not the issue, but I am going to check the exact psi on the tires today just to be safe. I want to get everything lined up correctly with stance, then go from there. I found a drive line specialist in Springfield, Mo (40 miles from me) that can just make the B&T disappear, balance the shaft and go through the U joints. He quoted me approx $200 for the job. Might do that for peace of mind after I crawl around under the dart trying the washer trick. I'll know more after I drop that drive shaft and inspect the converter for any weights that might have dropped. Some converters are weighted according to a specialist I talked with. So, basically I'm going to line up propeller shaft to correct angle as directed by the official shop manual, translate the shaft aft with the washers on front B&T, replace shaft , drive. If problem goes away.... great! If, not I have talked to an auto trans specialist that knew the auto A-904 trans and will drive dart and make recommendations for free. He said some converters are waited. Can't hurt. That is the plan. We'll see. just takes time. I'm not buying anything until I feel safe under the car using jack stands. I'll use huge cardboard flat boxes, that I have, to scoot around on floor. I'll borrow torque wrench from auto parts store when I put the propeller shaft back in car.
 
Total incompetence is what I've been dealing with! Now that I've started looking things over, I'm just floored at the level of quality care. The trans dip was out of it's hole and dangling by a spark plug wire. The leaf springs were totally loose. They basically were just hanging there by a prayer. There were missing nuts on the leaf spring brackets that attach to the structure. I'm not sure they did anything except replace the spark plugs. Good god, what a nightmare. I'm calling and complaining. I will be tightening and checking everything mentioned in this forum. I still have the vibration, but now I can take control. Wow!
 
I paid a garage once,to replace a distributor. I could have bought a manual,tools and a good timing light for what i paid. Thats where this mess started. 30,000 plus in tools and i now fix cars for a living. With integrity. Had i not found the problem, you would have paid for plugs and a fair price to change them.
I told a customer if i cant fix his no start escape it would be no charge. Determined to figure it out, i started pulling plugs,wet and had compression and spark.
Plugs were wet-water wet.
Turns out his employee used gas from a boat instead of buying gas. Guess what? Boat doesent run either.figured out the escape and fixed the boat without even touching it. Big load of water.
Spent too many years working around incompetent people,so i took matters into my own hands.

Also turns out i dont play well with others. Guess my kindergarden teacher was right.

Has to be something causing your vibration, im sure you will find it. I'm rootin for ya!!
 
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Vibration story of my own. I had a my 65 on a side street driving home one night and I startred from a light. I felt a little shudder ans it passed. I then stopped at the next light and it came back again but stronger. NOW I'M LIKE WTF. So I take off a third time and the **** hits the fan at about 20mph. Ever see a grocery cart front wheel wobble? Thays what my entire front end was doing, it about rattled the mirrors off the car. I hit the brakes and it went away but I couldn't drive faster than about 15 or I'd get the shimmy back in a violent way. For it home and checked it out. Turns out the K member was cracked in 2 of 3 mounting points of the steering box. Another shimmy session and it would have let go completely. I found a 65 K about 200 miles away already pulled and painted so I made the trek and was home by noon, had it R&R'D in about 2 hours with the help of a cherry picker and some less than safe under the sling work. Problem solved. Good luck, let us know what the problem was after tou get the reason suspension torqued down.
 
jeffrey356 said:
Killer6, I have brand new Kelley tires on the Crager Mags. Probably not the issue, but I am going to check the exact psi on the tires today just to be safe. I want to get everything lined up correctly with stance, then go from there. I found a drive line specialist in Springfield, Mo (40 miles from me) that can just make the B&T disappear, balance the shaft and go through the U joints. He quoted me approx $200 for the job. Might do that for peace of mind after I crawl around under the dart trying the washer trick. I'll know more after I drop that drive shaft and inspect the converter for any weights that might have dropped. Some converters are weighted according to a specialist I talked with. So, basically I'm going to line up propeller shaft to correct angle as directed by the official shop manual, translate the shaft aft with the washers on front B&T, replace shaft , drive. If problem goes away.... great! If, not I have talked to an auto trans specialist that knew the auto A-904 trans and will drive dart and make recommendations for free. He said some converters are waited. Can't hurt. That is the plan. We'll see. just takes time. I'm not buying anything until I feel safe under the car using jack stands. I'll use huge cardboard flat boxes, that I have, to scoot around on floor. I'll borrow torque wrench from auto parts store when I put the propeller shaft back in car.
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Don't forget what I mentioned about the engine year, if it has been replaced by a '68 or newer mill, the crank register is too large for the '67 and down converter hub. Again,
this would be an engine speed, not vehicle speed related vibe, but w/o a hub-ring to center the converter it may cause some eng. vibes.
 
Killer6, I believe everything is original to '65, but I gotta sneaking feeling that it's going to end up to be the converter, flex plate, etc.. Lord, I hope not. I'll try everything else first. Pishta, you scared me. I took the dart to the car wash and cleaned the engine. All the grime was hiding the mounting fasteners for the steering box. Cleaned it up and tightened bolts and inspected the K member. I didn't see any cracks, but if I do find cracks, can it be welded for structural integrity?
 
Those idiots! Before washing grime away, I noticed that the engine mounts hadn't been touched. The drum brakes still pull to the right. They did the brakes months ago and I asked them to kindly fix what they missed and they didn't do it. WTF! What is wrong with people. Taking advantage of those people with disabilities is wrong. They made me look like a complete dumb ***. I'll never trust them again. I have found other specialist that will inspect things free of charge after I do what I can. I can't drop the trans, but I can inspect and tighten mounts. I just hope it doesn't come down to be the converter or harmonic balancer. That's expensive! Everything else is reasonably priced. UGH!
 
jeffrey356 said:
Those idiots! Before washing grime away, I noticed that the engine mounts hadn't been touched. The drum brakes still pull to the right. They did the brakes months ago and I asked them to kindly fix what they missed and they didn't do it. WTF! What is wrong with people. Taking advantage of those people with disabilities is wrong. They made me look like a complete dumb ***. I'll never trust them again. I have found other specialist that will inspect things free of charge after I do what I can. I can't drop the trans, but I can inspect and tighten mounts. I just hope it doesn't come down to be the converter or harmonic balancer. That's expensive! Everything else is reasonably priced. UGH!
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Well, You got out of there only out $100, these days that's nothing so don't let frustration get the better of You. The brake pull could be bad upper control arm bushings
besides the list of actual brake related causes, or even the rear axle shifting and steering the vehicle if it is not secured or has worn bushings etc. Don't get ahead of
Yourself and imagine the worst, correct what You find one item at a time, and move methodically to the next item. Once You've gotten obvious things like visibly loose
and worn out things tightened/replaced, go back to test drive diagnosis as stated to isolate where the issue lies.
 
Yes, starting from ground zero. Bought jack stands and creeper on sale at tru-value. All for under $55. The creeper is cool it unlocks and becomes a seat for when you pull those wheels and do your own drum brakes. If I still had my wife, she could help me bleed the brakes and help out with other things. She helped me put the engine back into good sorts after I bought it. I miss her.
 
jeffrey356 said:
Yes, starting from ground zero. Bought jack stands and creeper on sale at tru-value. All for under $55. The creeper is cool it unlocks and becomes a seat for when you pull those wheels and do your own drum brakes. If I still had my wife, she could help me bleed the brakes and help out with other things. She helped me put the engine back into good sorts after I bought it. I miss her.
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Lesson learned from creeper seat. There is a strap, used for raising and lowering it to creeper mode. One hand on latch, other on strap. Dont learn the hard lesson. It hurts.
 
Bahhh....read though this whole thread like it was current... (I need to read the "date" first)
Looked up Jeffery356... not seen since May25, 2019....
Oh well... read though it at Dunkin Donuts... and Two Large Coffees
LoL
 
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