Drivetrain 89 GT, Whining/whirring from trans with clutch engaged

[FetusLasVegas]

The last two times I've driven my car, I started to notice a blower like whine coming from the trans. It happens with the clutch engaged and the car moving, under deceleration or coasting. It increases/decreases according to rpm. With throttle input it seems to go away, or is not as bad. In first gear it just sounds like a blower, in second gear it gets louder and a little more offensive, in third gear, it sounds completely awful and is the loudest. I'm typically under steady throttle input in 4th and 5th gears, so haven't noticed it really then. I don't know if it's related, but it also popped out of first gear twice yesterday, once while slowing down for a red light, and once under slight deceleration pulling into a parking garage.

I really tried to pay attention to it on my way home last night. When shifting into first from a stopped position I can hear a faint whirring coming from the shifter as I shift into first. It seems to get quicker/slightly louder as I push the shifter into first, and then die off when it's fully shifted. The entire time I've had the car (almost a month), I have had some difficulty shifting the car into reverse. I shift into 4th first and then to reverse. Sometimes it shifts fine, others I have to blip the throttle to get it to seat in reverse.

From everything I've read, it looks most likely to be a problem with the pilot bearing, although I've read conflicting info on this. I don't think it's the throw off bearing because it only happens with the clutch engaged.

Thank you!!!!

 

[General karthief]

Do you know if the clutch has ever been replaced?
if it has a lot of miles a rebuild is in order, that includes the trans. It could be a pilot bearing but your not going to tare it all apart to just fix that,

 

[FetusLasVegas]

I’m not too clear on the history of the car. It supposedly has around 60-70k. Aside from the obvious annoyance, should I be worried or not driving? Is there anyway to troubleshoot and find out what the problem is so I can fix it??

 

[JD1964]

Have you checked or changed the fluid? I'd drain it, refill with full synthetic auto trans fluid like Mobil1 or similar. It might help, especially if you are running low fluid that has never been changed. Sometimes cars get regularly parked on dirt or gravel instead of pavement. When this is the case, owners may not be as aware of leaks.

 

[FetusLasVegas]

I have it parked in my garage. I know it leaks a little oil. The previous owner said the rear main seal likely needs replacing. I haven’t noticed any trans fluid on the floor.

I will drain and replace the fluid tomorrow and see if that helps. Should I use a trans stop leak product or is that not recommended?

 

[FetusLasVegas]

Got under it for first time today. New leak I haven’t seen on the car before. Almost milky white translucent fluid.

No idea what it is. I’m about to drain and change the trans fluid. I’ll follow up after.

 

[JD1964]

That milky look can indicate water or moisture. Check for coolant leaks too. Maybe do a pressure check on the coolant system. Just asking but did that car ever live in a flood prone area.

 

[FetusLasVegas]

I know basically nothing about the history of the car... but it’s been very rainy here so water dripping off the car most likely mixed with whatever fluid leaked.

My trans was pretty much bone dry. Only a handful of drops of fluid drained out. Luckily I only drove it less than 30mi since it was sounding bad.

Refilled trans with 3 quarts of Castrol mercon v. That didn’t top it off. I will add more tomorrow. After filling I left the car lifted for a bit to inspect for leaks. There is a decent leak, about one drip every minute or so. I can’t tell exactly where it is coming from. It looks to be from the far tail end of the trans. Here is a pic of where the drips are forming:

Took her for a test drive. The horrible noises and whining are gone. I hope I didn’t do too much damage while the fluid was low/gone.

As for fixing the problem, I have no idea where it’s leaking from. I have a decent floor jack and jack stands to get under the car, but my flashlight died when I was trying to inspect. Can/should I use a trans stop leak product? Anyone had a leak in this area before have any insight??

 

[JD1964]

That looks like it might be dripping down from the driveshaft yoke seal. Not too difficult to fix if that's it. Pull the driveshaft, pull the old seal and tap a new one in, reinstall driveshaft. Good time to check the ujoints out too. Might even be worth replacing them. If you want you can take the shaft to a shop and have them put the joints in, then you put shaft back in car. If you've never done ujoints before and dont have a decent good sized vice, they can be a little tricky to get just right. Also check where the speedo cable hooks up on the tail passenger side. It's another common place for a leak.

Crazy how there was no fluid in there huh?

Oh yeah, if you do the driveshaft, or get someone else to, make sure the driveshaft bolts and holes get cleaned really good. Then use loc-tite on the threads when you put them back in.

 

[JD1964]

I would avoid using stop leak. Instead, go back under there and spray it all clean with brake cleaner. Then watch for leaks to see if you can pin point them. If the car is tilted back when lifted, that should push more fluid to the rear and initiate a leak so you can find it.

 

[JD1964]

Correction, I stated Speedo cable on passenger side. It’s actually on the drivers side of the tail

 

[FetusLasVegas]

Well, I topped it off today and cleaned up the tail end. I gave the driveshaft a firm shake and it doesn’t move at all without the trans moving with it.

There doesn’t seem to be any leaking from the yoke seal. The speedo cable is currently disconnected, but there doesn’t appear to be any leak from where it connects to the trans either. The fluid seems to be coming from the top side closer to the engine than the speedo connection. I couldn’t get a pic as I had to wrap up pretty quickly and leave.

Let me know if any of this helps, if not I will try to get some pics later tonight or in the morning.

 

[JD1964]

There’s a seal where the shifter assembly bolts up on top. But that wouldn’t leak just sitting there. You’d have to drive it and churn the fluid up top to get it to leak

 

[FetusLasVegas]

There’s a seal where the shifter assembly bolts up on top. But that wouldn’t leak just sitting there. You’d have to drive it and churn the fluid up top to get it to leak

The front end is lifted a good 20” over the rear as it’s currently on jack stands in the front only. I don’t know if that would make a difference. But I think it is still leaking off of the stands as well. Anything else up there it could be leaking from?

 

[FetusLasVegas]

All dry on the tail end.

Here is below where it seems to be leaking:

 

[JD1964]

Looks like the gasket between the tail housing and gearbox is leaking

 

[FetusLasVegas]

Looks like the gasket between the tail housing and gearbox is leaking

Correct me if I’m wrong, but from what I’ve read, isn’t that sealed with permatex from the factory?

 

[JD1964]

Correct. And I believe you have to pull the trans to fix it. I had to change my speedo gear on the output shaft which required the tail housing be removed. I pulled the trans to do it. Clear all the old sealer away and clean surfaces. Put back together with new sealer. I think I waited at least 24hrs for the sealer to cure before I put fluid back in. Has not leaked a drop.

 

[FetusLasVegas]

Correct. And I believe you have to pull the trans to fix it. I had to change my speedo gear on the output shaft which required the tail housing be removed. I pulled the trans to do it. Clear all the old sealer away and clean surfaces. Put back together with new sealer. I think I waited at least 24hrs for the sealer to cure before I put fluid back in. Has not leaked a drop.

Can I just remove the driveshaft and pull the tail housing off the back to reseal it, or do I have to remove the entire transmission?

 

[rc46joe]

If you pull the trans you could do the rear main seal as well. Probably wouldn’t hurt to have someone go through the trans. If it was that low it’s probably been low for some time.