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iTrader: (2)

well here is the story. end of last season i blew my trans so over winter i bought a heavily built 4l65e from a performance shop near me and also bought a new Yank3600. I got them installed and put on around 175 break in miles through-out neighborhoods so 35mph and below, noticed vibrations here and there but never seemed bad and i thought some of it was due to my xpipe dumped before the axle or bad tore up roads from winter. i got my true dual finished and have been driving it a lot more now that its semi quiet now and have been venturing out in main roads that allow me to cruise at various(35-55mph)speeds. Ive noticed the vibration is pretty bad in any gear over 3500rpm. it does NOT vibrate in park or neutral. i loaded the converter to 2500ish and it did not vibrate.....so heres what i did... I pulled tires and ran it on jack stands and vibration was still there. Pulled drive-shaft and inspected and rotated 180* vibration was still there. Unbolted converter and rotated 120* and vibration was still there and didn't seem to change at all.. im completely lost on what to check next? Could it be the trans causing a bad vibration like this? i did not have any problems with my previous setup edge3400 and tci rebuilt 4l60e trans.

so to sum it up have bad vibration any drive gear(1-4, not park or neutral) above 3500 rpm
ruled out tires
inspected drive-shaft
think i can rule out converter

Any advise or tip would greatly appreciated

mrvedit

Have you tried it in Reverse?
Are you sure the nose of the converter is properly seated in the pilot hole of the crank?
Are you sure the vibration is tied to engine RPM and not driveshaft speed?

It does sound like a tricky one to diagnose.
Anyone have other ideas ???

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iTrader: (2)

Yes the converter is seated correctly, i did have to use washer shim to get he pull back within yanks instructions specs. And yes it rpm not speed, I can be at 4k rpm in 3rd and it will be vibrating like hell and then shift to od and the vibration goes away.... One thing that I Made note of when i was under the car was the trans output shaft had a lot of play in it(like a joystick not In and out) is that normal?

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iTrader: (2)

Can an internal issue with the trans cause this problem???

Go On 3

iTrader: (2)

No I haven't tried it in reverse, didn't really want to push reverse to 3k rpm, seemed like a lot of rpm and mph for reverse but if its safe to do I will try it

mrvedit

If with the shifter in Park you can rev the engine above 3500 without vibration, then the converter should be fine because it spins at engine speed. The same is true for a large assembly of the trans called the input drum. (But see below)
About the only part of the trans that could cause a major vibration is the sun shell, but that only spins in 1st and 3rd gears.

After that there is only the output shaft, drive shaft and rear end. However those will vibrate in relation to vehicle speed.

Please describe the play in the output shaft - and out by .030 is normal.
Also how can you tell - the output shaft is not even visible except for the very end?

Just a wild guess, but if this vibration only occurs in Drive, I wonder if a problem in the input drum or front planetary could be the culprit. Knowing if it vibrates in Reverse would help - the forward clutches are then not engaged.

Go On 3

iTrader: (2)

When I pulled the drive shaft I wiggled the output shaft, it moved atleast a half inch in all directions except in and out

mrvedit

I'm, pretty sure that is your problem.

I'm not an expert - I only rebuild my own transmissions several times a year to test different aftermarket parts and experiment. However I have never noticed any side-to-side play in any of my output shafts.
The inside end of the output shaft fits into a recess in the input drum and is up against a torrington bearing.
That looseness will cause the output shaft to wobble and get all the internals out of balance.

It sounds like the rearmost case bushing was left out.

Frank (Performabuilt), CarsonAuto, MontCarGuy or any other builder, please confirm.

performabuilt

iTrader: (25)

A small amount of movement in the output shaft is normal but not 1/2 inch just a tiny bit hardily noticeable amount with the drive shaft installed. Now you will have a good bit without the yoke in trans as the tail housing bushing is what supports both the output shaft and the yoke. If you have a lot with the yoke installed I would say the tail housing bushing and or drive shaft yoke has excessive wear.
On thing to note if you have chosen to run poly mounts on engine or trans or both you will have vibration period and it will be more pronounced in third gear, Just a note there,

02TA_RamAir

The output shaft will move quite a bit without the yoke installed, but to move a half an inch is even more odd. The transmission yoke thickness is only about .2" so that would be the absolute most it could move (nowhere near 1/2"). What clearance did you have with the yoke installed (there will be a very small amount). The input shaft/drum is positively hooked to the forward end of the torque converter so since it didn't vibrate when you revved it in park, that should rule out the input shaft/drum. If you put it in reverse, the reverse input drum and lo/rev clutches are active and the input drum will spin (no clutch engagement) as well so that should tell if they are in balance (try it on jack stands).

Go On 3

iTrader: (2)

Haven't had much time to under the car lately but as I was finishing up exhaust tonight I tried to wiggle the driveshaft while it was installed and it was pretty firm not really any play at all with it installed

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iTrader: (2)

Ill get it back up on stands tomorrow and see what it does in reverse,

Go On 3

iTrader: (2)

Got the car up on stands today and it does NOT vibrate in reverse.... any more insite would be greatly appreciated...im so frustrated with this im half tempted to sell the car and buy a prius lol
the shop i got the trans from gave me a spare converter to swap in to see if it is the yank 3600 that is my problems...

mrvedit

Vibrations can be difficult to pin down, but I don't think it is the converter.

With no vibration in Neutral and Reverse, as 02TA_RamAir explained, you have now tested everything other than the forward/overrun clutches in the input drum and the forward planetary set. And I think that is where the problem is....

The output shaft is clearly too loose. The front of it connects to the front planetary assembly, whose outer gear engages into the 3-4 clutch frictions. In the forward gears only this planetary assembly is starting to wobble when the input drum is spinning fast enough.

Ha - I think I know what the problem is. You mentioned it was a 4L65E, which means it has 5-pinion planets. A few years ago GM/ACDelco changed to a newer style 5-pinion planetary which IS NOT backward compatible with older transmissions UNLESS the updated Reaction Carrier Shaft and corresponding bearing are also used. I documented this fully with pictures in my post #12 in this thread:

https://ls1tech.com/forums/automatic...n-planets.html

The rest of the thread goes into more details.

Otherwise, nothing centers the planetary assembly and it will wobble sideways moving the output shaft with it. (There is plenty of side-to-side play within the 3-4 frictions to allow that.)

So if the trans builder bought a new 5-pinion planet and didn't also update the correct bearing and reaction carrier shaft, that IMHO would be consistent with your symptoms. I would suggest asking your builder to review that thread.

Ted.

Go On 3

iTrader: (2)

Now we're cooking with peanut oil!!!!! Thanks for the help ill contact the builder in the am and keep u updated with what he says( I really hope this is the issue because I really do not want to pull the trans to put another converter in)

Go On 3

iTrader: (2)

Builder just got back to me and he said he used the stock 5planetary

mrvedit

So it was a factory 4L65E that he rebuilt using the same planetary parts?

I still think the problem is in the trans, in the area of the front planetary, and your builder should be taking care of it.
Trying out another converter is a big job, about the same as removing and installing the trans. It should barely take a trans builder an hour to open up a recently rebuild trans and figure out why the output shaft is so loose, and/or confirm that the major components are assembled correctly.

I'm confident that if he confirmed your output shaft is as loose as you say it is, that he would want to open the trans.

Go On 3

iTrader: (2)

Yes it was a factory 4l65e, well talked to builder and he said he has no idea what could be causing the issue but he wants me to pull it and take it to him and he will look at it.

Go On 3

iTrader: (2)

well talked to the trans builder today he said he found one bushing alittle loose on the output shaft, he also said the reverse drum was wearing odd so he was going to replace that. He also sent me a pic of the input shaft and said that it had a odd wear pattern on it

does this look normal if not what could cause the this

mrvedit

The input shaft looks like the stator shaft is not square with the pump.
Mechanics sometimes replace the stator shaft by pressing the old one out of the pump and pressing in a new one. If not done perfectly, a tiny pit of metal scrapes off on the "key", lodges between the two and the stator shaft is no longer square, causing the input shaft and stator shaft bushing to wear.
With the builder saying the reverse drum was wearing odd, I would check this even more carefully.