Need to check my fluid level

[Timebender]

Hi guys,
I've come to discover that an ongoing leak I've been having, which a few of us (me, a mechanic buddy, some others) assumed was a main seal leaking (I have a Chevy 350 in the back). I had added some stop leak, but it kept leaking, and leaking. At times a few drips, and other times a lot of black oil- even after a few oil changes. What kind of was odd though to me, was that it seemed to leak more when I had been using the clutch and shifting.
And then at a certain point there'd be drips followed by a big puddle.

Yesterday I noticed after I shifted into first or reverse, there was a new sound I had never heard - not grinding, but the sound of gears until I let the clutch out all the way. There was no sounds in the other gears - just those two. And I also noticed the leak had stopped...

When I first got the cat back in January I had noticed at first a small leak, and then followed by a massive puddle in my garage on the same day. I had some other stuff to have looked at, so I shipped it up the coast to Danny. The good news is it wasn't the axle boots. He did find the clutch slave leaking and replaced that, and I had them also service the transmission (drain and refill) among a number of other things. He mentioned the black oil leak was coming from the valve covers.

So when I got it home, I changed the oil (it needed it and it was black), and replaced the valve covers (which may have been leaking a little but not puddle worthy). But still had the massive leak - and yet when checking the oil the levels really never went down - at all.

Questions:
Is manual trans fluid black? Or would it be black when leaking even after a change?

My car is lowered so I can't get really under the car far enough to get to the fill plug. I'm guessing I have to jack it up in the front (using the 2x4's to spread the load) or up some ramps and then jack up the back (same thing) to get under there? Or try and get to a local shop to get it on a lift and if so will that cause any damage?

I think that about covers it.

Thanks for any help!

[sdg3205]

New fluid isn't black, but used is not "as black" but that is also determined by how much dirt it accumulates before it drops and how old all your fluids are.

[David T]

New fluid isn't black, but used is not "as black" but that is also determined by how much dirt it accumulates before it drops and how old all your fluids are.

You can't tell the color well by what is on the floor. Once it leaks out and drips through all of the dirt it can get darker. Get the car up off the ground and check the level. If you haven't changed the transmission fluid in a long time or it is very low just dump it and fill with fresh. As for the motor check the oil sender on the LEFT side. Very common leak and and it looks like the pan gasket is leaking but that is only because of the way it drips all over.

[PJ Grady Inc.]

Hi guys,
I've come to discover that an ongoing leak I've been having, which a few of us (me, a mechanic buddy, some others) assumed was a main seal leaking (I have a Chevy 350 in the back). I had added some stop leak, but it kept leaking, and leaking. At times a few drips, and other times a lot of black oil- even after a few oil changes. What kind of was odd though to me, was that it seemed to leak more when I had been using the clutch and shifting.
And then at a certain point there'd be drips followed by a big puddle.

Yesterday I noticed after I shifted into first or reverse, there was a new sound I had never heard - not grinding, but the sound of gears until I let the clutch out all the way. There was no sounds in the other gears - just those two. And I also noticed the leak had stopped...

When I first got the cat back in January I had noticed at first a small leak, and then followed by a massive puddle in my garage on the same day. I had some other stuff to have looked at, so I shipped it up the coast to Danny. The good news is it wasn't the axle boots. He did find the clutch slave leaking and replaced that, and I had them also service the transmission (drain and refill) among a number of other things. He mentioned the black oil leak was coming from the valve covers.

So when I got it home, I changed the oil (it needed it and it was black), and replaced the valve covers (which may have been leaking a little but not puddle worthy). But still had the massive leak - and yet when checking the oil the levels really never went down - at all.

Questions:
Is manual trans fluid black? Or would it be black when leaking even after a change?

My car is lowered so I can't get really under the car far enough to get to the fill plug. I'm guessing I have to jack it up in the front (using the 2x4's to spread the load) or up some ramps and then jack up the back (same thing) to get under there? Or try and get to a local shop to get it on a lift and if so will that cause any damage?

I think that about covers it.

Thanks for any help!

It sounds like you have several leaks. Your most immediate concern would be "the sound of gears" which can quickly become grinding gears. If the master cyl. was not changed when the slave cyl. was replaced you are probably feeling the early symptoms of a leaking cylinder again. That's why it is recommended to change clutch cylinders in pairs if their age is questionable. Check for fluid seepage at the clutch master seal which you can see next to the accelerator pedal area inside the car. If it's leaking replace the master and the reservoir hose. Installing the braided stainless fluid line is advisable if yours is plastic.

You may have several other leaks. The best thing to do would be power wash the oily/dirty areas of the driveline and then add leak detection dye to the engine and transmission if necessary. Road test the car for 20 minutes or so and then check for the leak sources with a black light. Short of this diagnostic approach you will just have to keep replacing, the most likely to be leaking, gaskets and seals until all leaks are stopped or you are at least not getting any drips.
Rob

[Timebender]

Thanks guys. I did check the master and there are no leaks inside the car, and the fluid level under the hood is at full. Also, I replaced the oil pressure sender a while ago and it's nice and clean, so no leak there.

Also I still think there's something with the clutch area/rear seal, as whenever I put it in reverse, I do get a whiff of something heavy oily from the back of the car- not an engine oil smell, but a heavier weight thicker smell.

I'll get it on a lift or borrow some ramps and get it up this week to take a better look at the levels but my gut says it's low. And if so I'll dump it and refill, though as I mentioned supposedly Danny's shop did that before I got the car back a few months ago - at least I was charged for it.

Btw how many quarts do I need? And I know it's 80 weight here in California, but all they have at the Kragans is 80/90.

Greg

[DMC-81]

Btw how many quarts do I need? And I know it's 80 weight here in California, but all they have at the Kragans is 80/90.

Greg

Hi Greg,

You will need 4 quarts (7.82 pints or 3.71 liters). After a lot of research on hypoid etc, I bought Valvoline conventional High Performance 80/90.
37718

[DMC5180]

As for the motor check the oil sender on the LEFT side. Very common leak and and it looks like the pan gasket is leaking but that is only because of the way it drips all over.

David,

This does not apply here, he has a Chevy 350 conversion as mentioned in the 1st post.


Greg,

Generally speaking, Manual Transmission 80w-90 gear oil will not be black, but it can darken with age and use. It does have a strong pungent odor all it's own and is very distinctive. Pull the engine dipstick and smell the oil on the stick. Compare that smell with the oil dripped on the floor. If it's the same smell, it is an engine oil leak. If different, it is a Gear oil or Clutch fluid leak.

[Timebender]

Checked the clutch slave and no leaks there - which it shouldn't since it was replaced by Danny and Co. The stuff on the ground always seemed a bit thicker than 10w40, but I'll check what's in my drip pan vs. what's in the engine to make sure. And with all the oil I had been seeing, the level on the dipstick never got lower.

[DMC5180]

Checked the clutch slave and no leaks there - which it shouldn't since it was replaced by Danny and Co. The stuff on the ground always seemed a bit thicker than 10w40, but I'll check what's in my drip pan vs. what's in the engine to make sure. And with all the oil I had been seeing, the level on the dipstick never got lower.

Do the sniff test.

What about your transaxle flange seals? The FULL level is about and inch above the bottom of the axle flange seals. A torn or damaged seal can leak just sitting static.

[Timebender]

The look good, and Danny mentioned they weren't leaking when he had it in the shop. The leak tends to happen after the car is driven. If I clean up the mess after a leak, it doesn't leak afterwards. Also, the oil is typically all over the backside of the engine/oil pan, as if it's coming out from the tranny, hitting the flywheel and getting flung onto the engine. It's then dripping right onto the crossbeam and down to the floor from there. That's why we were kind of thinking it was the engine main seal that's been leaking.

[DMC5180]

Well if it dripping out of the flywheel housing then the most probable cause would be a rear main. Since you have a Chevy small block, rocker covers and the rear of intake manifold should be considered as possible suspects.


Dennis

[Timebender]

That's what I kind of figured. The cover seals were replaced, and nothing's coming out of the intake manifold. We had thought it was the rear main in the engine, but oil levels never dropped and now the leak has stopped, right about the same time as the odd sound when letting the clutch out in first or reverse.

[Timebender]

Did the sniff test today - the stuff in my drip pan is not only thicker, but dozens have near the same smell as the oil on the dipstick.

[David T]

Did the sniff test today - the stuff in my drip pan is not only thicker, but dozens have near the same smell as the oil on the dipstick.

Then it is probably the oil from the transmission. Check the level. If it is overfilled it can leak out the input shaft. There is another possibility. You have an engine swap. If the transmission is not EXACTLY centered to the crankshaft of the motor you may have damaged the input bearing and seal causing the leak.

[jwrayth]

If the inner O-ring on the output shafts has failed then gearbox oil can leak along the splined shaft and out of the roll-pins. I have observed that this can run into and contaminate the CV joints, and mix with the grease in there. This will then drip out as a black fluid mix of the gearbox oil and CV joint grease. This may be your scenario, but I would imagine you would see the distinct spray pattern from driving the car with contaminated CV joint grease. Not to mention the drips that form on the roll-pin.

[Timebender]

If the inner O-ring on the output shafts has failed then gearbox oil can leak along the splined shaft and out of the roll-pins. I have observed that this can run into and contaminate the CV joints, and mix with the grease in there. This will then drip out as a black fluid mix of the gearbox oil and CV joint grease. This may be your scenario, but I would imagine you would see the distinct spray pattern from driving the car with contaminated CV joint grease. Not to mention the drips that form on the roll-pin.

Overall around the CV joints where they connect to the trans it looks clean (and dusty too thanks to our dirt road). The leak is dead center below the bell housing/flywheel area. I don't believe it was overfilled -and I don't think Danny's guys would have overfilled it when they serviced it back in February (got the car back in June and have since only put a couple hundred miles on it). It was leaking badly when I sent it up in January, and still had it when I got it back - as the leak only happens from what I can guess is when using the clutch. The previous owner who's a mechanic never mentioned the leak, and I would also guess the original owner who had the conversion done didn't have a leak too.

I wonder if living on a dirt road with sometimes lots of variations (some small potholes or just washout from rain), could have upset the transmission and engine alignment?

[David T]

Overall around the CV joints where they connect to the trans it looks clean (and dusty too thanks to our dirt road). The leak is dead center below the bell housing/flywheel area. I don't believe it was overfilled -and I don't think Danny's guys would have overfilled it when they serviced it back in February (got the car back in June and have since only put a couple hundred miles on it). It was leaking badly when I sent it up in January, and still had it when I got it back - as the leak only happens from what I can guess is when using the clutch. The previous owner who's a mechanic never mentioned the leak, and I would also guess the original owner who had the conversion done didn't have a leak too.

I wonder if living on a dirt road with sometimes lots of variations (some small potholes or just washout from rain), could have upset the transmission and engine alignment?

Not knowing how they mated the engine to the transmission it is impossible to say. The original engine and transmission had hollow dowel pins to make sure everything lined up and stayed lined up. You can't count on just tightening bolts to hold them in position.

[Timebender]

I'm going to see if I can't contact the original owner and find out who did the conversion back in the Illinois area.