leaking trans at speedo cable
Thread Starter
Racer
Joined: Mar 2006
Posts: 493
Likes: 2
From: Dunellen New Jersey
leaking trans at speedo cable
The car has a thm 350 trans.It leaks fluid from the speedo calbe.also the speedometer stopped working.So... I checked the cable..Good.I checked the gear at the cable..good.I changed the o ring on the bullet shaped thing and it still leaks.One thing be fore and after I chenged the oring the bullet is loose.I tightened the 7/16 bolt as tight as it goes but it still is unusually loose.I'm hoping this is the reason the the gear may not be touching the other gear and this may be the reason it leaks.The just stopped working as I was driving.Why would this be loose?I have a 400 trans on the side and its in there tight.
Instructor
Joined: Sep 2010
Posts: 229
Likes: 1
From: Grants Pass Oregon
The car has a thm 350 trans.It leaks fluid from the speedo calbe.also the speedometer stopped working.So... I checked the cable..Good.I checked the gear at the cable..good.I changed the o ring on the bullet shaped thing and it still leaks.One thing be fore and after I chenged the oring the bullet is loose.I tightened the 7/16 bolt as tight as it goes but it still is unusually loose.I'm hoping this is the reason the the gear may not be touching the other gear and this may be the reason it leaks.The just stopped working as I was driving.Why would this be loose?I have a 400 trans on the side and its in there tight.
Is the bullet the stock aluminum one ? If so, they do wear out. Best to replace with new steel one. Pull the bullet out and with flashlight, look and see what the drive gear looks like, also see if you can turn it by hand. When mine stopped working, i pulled tail shaft housing and my drive gear was warped. I replaced bullet,drive and driven gears. Speedometer worked great.
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,118
From: Crossville TN
Did you connect a variable-speed drill up to the trans end of that cable and run it slowly to see if your speedometer would provide a reading? That would tell you if the cable and speedo were 'good' or not. Also, the outer end of the speedo driven gear (in that 'bullet') can split so that the square end of the cable will not actually turn, even though it is installed properly in that gear. Look closely and maybe pry around with some needle-nosed pliers to be sure the gear is good.
Thread Starter
Racer
Joined: Mar 2006
Posts: 493
Likes: 2
From: Dunellen New Jersey
I spun the cable and the gauge works.Just couldn't figure out why the cone was still loose even after I tighten the bolt all the way.The pinion style gear looks good.I suspect the ring type gear inside the trans is bad.I'm taking it to a trans guy.I'm so done with this car.
Intermediate
Joined: Jul 2010
Posts: 28
Likes: 1
I had similar problem with leakage although my tranny is a 700r 4 speed automatic, same issue nonetheless. While I had him fix this, I decided to get entire thing rebuilt and new shift kit, lockout, upgraded stall converter in...no leaks, life is good now ;-)
Instructor
Joined: Sep 2010
Posts: 229
Likes: 1
From: Grants Pass Oregon
I spun the cable and the gauge works.Just couldn't figure out why the cone was still loose even after I tighten the bolt all the way.The pinion style gear looks good.I suspect the ring type gear inside the trans is bad.I'm taking it to a trans guy.I'm so done with this car.
Are you sure the 'clip' is locked in the groove when you tighten the bolt? With the bullet in, you can take a small screw driver, see if you can turn the gear.If so,then drive and driven gears don't mesh.
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Thread Starter
Racer
Joined: Mar 2006
Posts: 493
Likes: 2
From: Dunellen New Jersey
The trans is a new TCI unit.I changed the outside o ring but it my be the one on te gear shaft like wombvette says.the clip gets tight but the cone was still loose.I bent the clip slightly and it tightened it good.Don't know if it stopped leaking yet.I'm taking it to a trans guy.
