Keisler Vibration
Thread Starter
Le Mans Master
Joined: Aug 2000
Posts: 6,273
Likes: 14
From: Austin TX
Strange Vibration after Keisler Installation
Normal installation, sent drive shaft back for balancing and smaller u joints.
Operation seems normal except for vibration coming through the shift lever at around 4000 rpm in any gear.
Any idea as to what is causing this?
Operation seems normal except for vibration coming through the shift lever at around 4000 rpm in any gear.
Any idea as to what is causing this?
Last edited by flynhi; Apr 25, 2006 at 11:27 AM. Reason: Inadvertent Indictment of Keisler
Melting Slicks
Joined: Dec 2005
Posts: 2,441
Likes: 0
Originally Posted by 694speed350
also could be from the drive shaft. contact keisler and tell them about the problem.
Try revving it up to 4 grand in the driveway, if you feel the vibration there its definitely in the engine/flywheel/clutch assembly.
Last edited by shafrs3; Mar 18, 2006 at 10:57 PM.
Melting Slicks
Joined: Nov 2004
Posts: 2,540
Likes: 1
From: Pineville Kentucky
CI 6-8-9 Veteran
Originally Posted by flynhi
The vibration is not real bad but definitely not normal. Mostly "feelable" through the shifter handle.
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Burning Brakes
Joined: Sep 2004
Posts: 1,224
Likes: 49
From: Ventura Calif
Take the drive shaft to your local drive shaft (driveline) builder and have him check the balance. An unbalanced drive shaft will only vibrate badly at a resonance frequency (speed). Keisler shipped a lot of unbalanced drive shafts for a while and never recalled the suspected ones! 
Last edited by JohnFromVentura; Mar 18, 2006 at 10:43 PM.
Le Mans Master
Joined: Jul 2005
Posts: 5,752
Likes: 4
From: Austin Texas
Originally Posted by JohnFromVentura
Take the drive shaft to your local drive shaft (driveline) builder and have him check the balance. An unbalanced drive shaft will only vibrate badly at a resonance frequency (speed). Keisler shipped a lot of unbalanced drive shafts for a while and never recalled the suspected ones!
Former Vendor
Joined: Apr 2002
Posts: 534
Likes: 2
From: Cookeville TN
Originally Posted by JohnFromVentura
Take the drive shaft to your local drive shaft (driveline) builder and have him check the balance. An unbalanced drive shaft will only vibrate badly at a resonance frequency (speed). Keisler shipped a lot of unbalanced drive shafts for a while and never recalled the suspected ones!
John this has been addressed SEVERAL times already. About 9 months ago we did find out that we were getting some drivesahfts that were not properly balanced. Mr Keisler, who is an engineer, went to the driveshaft manufacturer and personally inspected their balancing equipment. He found that one of the machines had a part that was out of spec, and some of the shafts spun on that machine were not balanced properly. This was corrected and the company put new Q/A guidelines in place to prevent the problem from recurring.
Only a few customers received defective shafts. Any customers who had problems received a new driveshaft or we paid to have theirs balanced.
Drifting
Joined: May 2005
Posts: 1,257
Likes: 0
From: calgary alberta
Originally Posted by Robert Hall - Keisler Sales
John this has been addressed SEVERAL times already. About 9 months ago we did find out that we were getting some drivesahfts that were not properly balanced. Mr Keisler, who is an engineer, went to the driveshaft manufacturer and personally inspected their balancing equipment. He found that one of the machines had a part that was out of spec, and some of the shafts spun on that machine were not balanced properly. This was corrected and the company put new Q/A guidelines in place to prevent the problem from recurring.
Only a few customers received defective shafts. Any customers who had problems received a new driveshaft or we paid to have theirs balanced.
flags you could have tried answering his question just a thought
Race Director
Joined: Feb 2005
Posts: 16,100
Likes: 17
Yeah..let's get back on topic..
It could be shift linkage bushings...or some "hard" bushings somewhere transmitting more vibration to the shifter...you might check shift linkage bushings first..to see if they are "hard" or soft...then look at tranny mount...
My 78 shifter "buzzes" at 3500 rpm in 4th only...so I just speed up..or drive just below...but know my shift linkage bushings/shift rod seals need replacing...
It could be shift linkage bushings...or some "hard" bushings somewhere transmitting more vibration to the shifter...you might check shift linkage bushings first..to see if they are "hard" or soft...then look at tranny mount...
My 78 shifter "buzzes" at 3500 rpm in 4th only...so I just speed up..or drive just below...but know my shift linkage bushings/shift rod seals need replacing...
Melting Slicks
Joined: Dec 2005
Posts: 2,441
Likes: 0
Originally Posted by rihwoods
Yeah..let's get back on topic..
It could be shift linkage bushings...or some "hard" bushings somewhere transmitting more vibration to the shifter...you might check shift linkage bushings first..to see if they are "hard" or soft...then look at tranny mount...
My 78 shifter "buzzes" at 3500 rpm in 4th only...so I just speed up..or drive just below...but know my shift linkage bushings/shift rod seals need replacing...
It could be shift linkage bushings...or some "hard" bushings somewhere transmitting more vibration to the shifter...you might check shift linkage bushings first..to see if they are "hard" or soft...then look at tranny mount...
My 78 shifter "buzzes" at 3500 rpm in 4th only...so I just speed up..or drive just below...but know my shift linkage bushings/shift rod seals need replacing...
Race Director
Joined: Feb 2005
Posts: 16,100
Likes: 17
Originally Posted by shafrs3
Easier said than done, the linkage is internal in these boxes.
Thread Starter
Le Mans Master
Joined: Aug 2000
Posts: 6,273
Likes: 14
From: Austin TX
Ran it up inthe driveway today. Slowly revved from idle to 4000 with shifter in neutral.
Vibration is felt though the seat and floor boards starting at about 2700 and gets progressively worse. Not real bad at 4000 but definitely not normal.
So, I'm guessing it's the flywheel.
Vibration is felt though the seat and floor boards starting at about 2700 and gets progressively worse. Not real bad at 4000 but definitely not normal.
So, I'm guessing it's the flywheel.
Melting Slicks
Joined: Dec 2000
Posts: 2,130
Likes: 1
From: mesa,az
interesting, i have a vibration around 3000 RPM. nothing major but it's there. while i also have a keisler tranny i don't know what it is. for all i know i have a tire out of balance. still driveshafts, flywheels, clutch plates. there is a LONG line of suspects and to tell the truth it's not enough for me to bother chasing right now.
Burning Brakes
Joined: Sep 2004
Posts: 1,224
Likes: 49
From: Ventura Calif
Wonder if you had the flywheel and clutch balanced while you had it apart? My ballancer says that normally Centerforce clutches are on the money but ocassionally finds one that is off. Did you dial in your bellhousing? I'm thinking about a Tremec for my 68. 