How much trans yoke "play" is acceptable?.....FIXED!

[Just 6T9 CHGR]

Underneath the car today "just checking" and pushed/pulled on the trans output side of the yoke.....damn she really moves around in there!

Im gonna estimate about 1/4" movement/slop up & down.

is this too much?   What usually gives out first the yoke splines or the output shaft?  Which is the sacrificial part?

[Charger-Bodie]

i personally would say thats too much, i mean they do have a fair amount but that seems excessive. does it vibrate at all?

[Just 6T9 CHGR]

Yes, that was my main reason for the "just checking"

Ive had a vibration at around 60-70 mph for a while now.   Put a new trans mount in a few years ago and it got "better" but is starting to come back again.
was reading up on driveline angles etc and tried an easier washer-between-the-transmount-and-trans approach.....hard to tell but it seems a bit better on my short test run.
Im wondering if this slip yoke could be contributing?

[Chryco Psycho]

there is a bushing just inside the tailshaft behind the seal that seems to need to be replaced

[resq302]

   I was told that in the tail shaft of the trans, there is a brass bushing that ususally wears which gives you an excessive amount of play.  If you pull out the seal, you can take a light and look in and see it with the drive shaft removed.  There are grooves in the bushing that are there for trans/gear lube passages.  I was told by a trans shop that when those bushings go bad, you will not be able to see any more of the grooves.

[firefighter3931]

Pull the tailshaft and install the new bushing. 


Ron

[Just 6T9 CHGR]

I dont know guys, I think I'm just looking for problems.   I puled out the drive shaft last night & checked the movement of the output shaft.....not even close to the movement with the slip yoke on.   I tried a spare driveshaft I had and it had the same movement as the original one.
I think the movement I have is "normal"....I must restrain myself from looking for trouble!

[8WHEELER]

I think the movement I have is "normal"....I must restrain myself from looking for trouble!

But still find the vibration problem   

Does the vibration feel under your but? or futher back? did you have your shaft balanced?
Normally people don't bother balancing there shaft, but if you have a vibration, check into it 

Or if you need a bushing, here ya go... http://cgi.ebay.com/ebaymotors/NOS-Mopar-833-727-Seal-Boot-Bushing-PROBLEM-SOLVER_W0QQitemZ280117094714QQihZ018QQcategoryZ34208QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

Dan

[Just 6T9 CHGR]

Dan, the vibration is varying.......sometimes I feel it in the steering wheel, other times in the middle of the car.......hard to pinpoint.  I never feel it in the shift lever though.
The shaft is new (about 4 years old) changed it because the old one was suspect of a vibration.  I had a new tube built up but used the same slip yoke.

I've pretty much had this vibration through 2 engines as well......I'll find it

[Charger-Bodie]

Chris one VERY overlooked problem that can cause a vibration in the steering column is that somtimes when people install the column they push it down tight so that the wedges in the steering coupler are tight in the botom it needs to be able to give both ways and cant if thats the case....this may be somthing you already checked or known about if so disregard but its one of those easy to overlook deals.

[firefighter3931]

but used the same slip yoke.

I've pretty much had this vibration through 2 engines as well......I'll find it

Chris....what's the history on the front yoke ; how old is it, how many miles ?

It might be worthwhile to run a mic on the yoke to see if it's within spec or just undersized from excessive wear. Just a thought 



Ron

[Chryco Psycho]

1/4" verticle movement in the slip yolk ids excessive in my opinion & will cause a vibration , it should be snug in there

[Just 6T9 CHGR]

A small update.......

I borrowed a friends driveshaft that had a 3 hour old yoke installed on it (thanks Ron ) and the "play" got 75% better.  Now it has what I would consider normal play.

His driveshaft was for a Dana so it was a bit shorter.....I was tempted to install it and take it for a test run but I figured the 1" or so shorter might  give me a false feel due to the yoke being further out of the trans.....

I will be ordering a new slip yoke from Mancini Racing and I will update when i put it in.

Thanks for all the help & suggestions!

[firefighter3931]

Cool....let us know how it works out 



Ron

[resq302]

I have had a vibration which I thought was the direct drive fan cause it only does it at a certain speed and RPM.   Mainly around 50-55 mph and 2500 rpms on the tach.  I checked the slip yoke and it now seems to have some movement in it so chances are it is worn.  I just had my trans gone over last year and basically just had a gasket kit put in as they said everything looked good.  Since I just had the carrier done, I dont want to mess up those bearings if the drive shaft is wobbling cause of the worn slip yoke.

The weird thing is if I go faster or slower than the above speed, the vibration goes away.  Vibration seems to be felt more through the steering wheel and front part of the floor pan.  The shifter also has some light vibration in it.

Thanks,

Brian

[BlueSS454]

Chris,

You have the same problem that the TH400 in my 70 SS Chevelle has.  The problem is the bushing in the tail shaft.  Mine begins to vibrate at speeds over 60 MPH and stops at 85-90 MPH.  I changed everything that could possibly cause a vibration, and the bushing is the last item on the list.  It's a cheap part and relativley easy to fix.

[Chatt69chgr]

That bushing has grooves in it to channel the lubricating oil to the machined surface of the slip yoke.  I would think that with the slip yoke fully engaged in the bearing that the vertical play should be negligible---just a few thousandths.  Best to mike the OD of the slip yoke to make sure it is in spec.  When you get the new bearing you can slide if over the yoke before you have it installed to see what the play is.  Assuming it's OK, then replace the bearing and seal.  I think you need a special tool to put in the bushing.  Probably a good job for a transmission shop.

[Just 6T9 CHGR]

Small update.   My cyclic vibration between 60-70 MPH is FIXED!

I ordered & installed a new slip yoke & the vibration is gone......no more woooh....wooh...wooh.   Now dont get me wrong the car isnt as smooth as a Lexus but it is 100% better than before.

I ordered the yoke from this seller on eBay
http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&ih=015&sspagename=STRK%3AMEWA%3AIT&viewitem=&item=250101852843&rd=1&rd=1

Turns out the yoke that Mancini Racing sells is from the same mfg as this guy sells.  Precision Industries.  I confirmed this by going on Precision Industries website, checking their part #, looking at my friends box that he got his in from Mancini & peeled back their label they put over Precisions & viola...same part # but $25 cheaper from this seller....

[firefighter3931]

Well that was an easy fix......which doesn't happen too often 

Glad to hear your ride is all well again ! 



Ron