MA87K5
1/2 ton status
4L60E tranny. Just rebuilt and now it shakes, but not at idle. Only after pressing the gas pedal. Doesn't matter if in drive or in park. What could cause this? I'm thinking converter wasn't balanced good enough. Thanks.
CK5
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tranny shake
- Thread starter MA87K5
- Start date
If you are noting a vibration through the vehicle that wasn't there prior to the trans installation there are a couple of things you can check. First, make sure the engine mounts are not broken. If the mounts are broken then the engine could have shifted during the trans removal and installation and you may have an engine or mount component touching the frame. Likewise, check the exhaust for any contact on the frame or crossmember, this can also set up a pretty healthy vibration. Third, have you gone to poly mounts on the engine or transfer case? These can set up a vibration you may not have felt previously as they do not quell vibration as well as rubber mounts will. If these all check out and there is no driveline to frame contact it is time to suspect the converter. Before you go to the trouble of removal, try clocking it at different positions on the flywheel to see if this helps. If not, pull it and ask for another from your builder.
MA87K5
1/2 ton status
Good idea on the different clock locations, didn't even think of that. Going to try that first. That's easier then moving the tranny. Might be able to try that this weekend. I do know it is a rotational vib though. Thanks
MA87K5
1/2 ton status
no luck on rotating the converter. I put another new converter in and still have vibe. Ran engine with converter unbolted and have no vibe. I'm thinking that there is something warped inside the tranny. Nothing was forced in during the assembly. Only clutches that I found were bad was for the low reverse. And they weren't evenly warn.
In 30+ years of transmission work I have never seen an internal transmission component cause a vibration. One reason you may not feel it when the converter is disconnected is that the engine is unloaded at this point and when you rev it , the engine moves more quickly thru it's rpm range. You need to be very careful with the throttle and bring the rpms up 50rpm at a time when looking for vibration with a disconnected converter. The side view mirrors are a good tell tale on slight vibration so check these frequently. There is no guarantee the second converter is in balance either, but that is kind of unusual, unless your converter builder is not balancing these or they have miscalibrated equipment. We have seen a lot of mass produced converters with serious imbalance.
MA87K5
1/2 ton status
It shakes like a tire is out of balance. Gonna get another converter. See if I can get one that was done on a different machine if possible.
I can check the balance on our equipment if you want to send me one of these. At least that way you will know for sure if it is out of balance. PM me and I will give you some shipping info if you want to do this, I won't charge you for it, happy to help.
MA87K5
1/2 ton status
Thanks, I am gonna try another converter first.
MA87K5
1/2 ton status
Put the 3rd converter and the vibe is almost gone.
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MA87K5
1/2 ton status
ya right lol the vibe is still there.
MA87K5
1/2 ton status
Update
Put forth converter in. This time it's a Recon rebuild one. Same problem. So there must be something wrong with the inside of the tranny. I have no clue what would be wrong.
Put forth converter in. This time it's a Recon rebuild one. Same problem. So there must be something wrong with the inside of the tranny. I have no clue what would be wrong.
I can promise you that it will not be inside the transmission so you can save yourself further aggravation and look into some other things that can cause this. We fix a lot of vibration issues by finding exhaust or engine components hitting the frame or body or some other component attached to the frame or body. Think of any other thing you may have changed recently, a fan, engine or trans mounts, (poly mounts can transfer far more vibration than rubber), exhaust components etc, and start retracing everything till you find the culprit. What engine are you using?
MA87K5
1/2 ton status
Nothing is hitting or rubbing anywhere. Doesn't shake with converter unbolted from flexplate. The olny thing I did different from the other rebuilds is put in a b&m transpak shift kit. It called for putting in a metal plug on the seperator plate and drilling a hole bigger. Valvebody wasn't touched. I'm starting to think that it is fluid related due to the shift kit. Maybe I read it wrong. Was way different then any other shift kit I installed. Thanks
