Shudder on hard acceleration from a dead stop 727.

[LittleSlantSwinger]

Hey guys so i cant find much online about this but i have a 72, swinger slant 6, 727 torqueflite automatic. And sometimes when hard accelerating from a dead stop it will shudder and shake the car. Only when at a dead atop as far as i know. But if i accelerate smooth and slow it wont do it? Im confused any info would be appreciated thanks!

 

[Projectile Dart]

Where do you think it's coming from specifically? Is the engine shuddering, transmission shuddering anything else?
If you have no idea I would look for worn out/broken motor mounts/ and transmission mount.
Does it only shudder under load or will it shudder in neutral if you Rev it up quickly?

 

[Demonic]

Mine did that behind my 383. Had over 150k on it at the time. A full rebuild with new bushings, clutches and bands cured it.

 

[LittleSlantSwinger]

Mine did that behind my 383. Had over 150k on it at the time. A full rebuild with new bushings, clutches and bands cured it.

Hmm interesting, you dont know what the exact cause was though. Im probabaly just gonna enjoy the car for now because all ive done is work on the dang thing lol. Vibration isnt horrible plus i cant afford a rebuild right now. Buuuut if anyone does know the cause for vibration on hard accel every now and then let me know! And thanks demonic.

 

[LittleSlantSwinger]

Where do you think it's coming from specifically? Is the engine shuddering, transmission shuddering anything else?
If you have no idea I would look for worn out/broken motor mounts/ and transmission mount.
Does it only shudder under load or will it shudder in neutral if you Rev it up quickly?

Not sure on the rev in neutral thing might try it. Also like i said only shudders on hard acceleration from a dead stop. And its hard to tell where it is at but it sounds possibly at the rear or somewhere around there. I retightend my lug nuts on the rear they were a bit loose and maybe that was why? Just converted the car from front drum to disc and havent driven it for a little while. Think im gonna test it tonight and find out if its still doing it. And maybe where its coming from.

 

[Bewy]

Engine mounts?

 

[Hellrats]

Clutches in the differential?

 

[Dubob]

Check mounts as stated. U joints good? Also check adjustment of kick down linkage. I say u joints because from a dead stop there is more load plus variance of pinion angle.

 

[RustyRatRod]

Worn leaf spring causing incorrect pinion angle would be my first guess.

 

[66signet]

I had a broken trans. mount do that.

 

[CudaFactHackJob]

Probably not inside the trans. Probably not a 727 trans..

 

[LittleSlantSwinger]

Okay everyone it might have just been my lug nuts lol. They were kinda loose in the back think that was my fault oops. Took it too test my brakes last night and accelerated pretty hard from a stop and didnt have a shudder so idk i guess its alright. Also love the fact that cuda said "probably not a 727 doing that" awesome transmissions.

 

[Righty Tighty]

Glad you figured it out and glad it was such a simple solution.