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Transmission Fluid - This Doesn't Look Good

12/08/2007


I finally got a break from work and started working on my cars yesterday.

First I changed the transmission fluid and filter in the 1998 car (51k miles). I pulled the cooler lines off to let the trans pump out its fluid. It pumped VERY slowly, just a thin trickle. The fluid started our pure black but after awhile it turned to a dirty red. The car worked fine after the change. The only problems the car had shown before was frequent torque converter locking/unlocking, I haven't driven it enough since the change to get it hot and determine if new fluid/filter fixed the problem, but the low rate of fluid flow doesn't look right to me. Does this mean I have to pull the end cover off and pull the pump out?

Secondly I changed the fluid and filter in the 1997 car (136k miles). This car is the one I am planning to sell. It has never shown any transmission problems, but it was time for the fluid to be changed and there was a slight fluid leak at the pan. I thought the only way I could cure the leak was with a new gasket, so I thought I might as well do the whole job. As I remembered, this car pumps plenty of fluid, and this is the third time I've done the full fluid change on this car.

Interestingly I noticed that both factory cooler tubes on the 98 are finned, whereas only the power steering cooler tube on the 97 is finned. With the slow rate of fluid flow in the 98 I'm not sure that the cooler would be effective.

The second time I changed the fluid in the 97 I added an auxiliary cooler. I threw in a photo of it just for grins
bj
       
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Your low flow rate could be as simple as a plugged filter.

That would be best case scenario of course....

Scott K
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I was hoping that, but it was the same before and after the filter change.

(Pump a few quarts out, change filter, add 12 quarts, pump most of that back out, the add 2 or 3 quarts to fill to proper level.)

bj
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That is the flow rate on the 98 when running? Yikes!

I would say the black stuff in the fluid was fairly abrasive and did
some harm to the pump vanes or pump bore and/or is also hanging them
up a bit still, so you are getting a lot of vane blow by in the pump.
The new fluid may help clean/loosen things up a bit but that doesn't
look very good.
A bottle of Lucas might help a little bit too.

Most importantly - how does it drive?

Eric Lehmann
97 Ebony 42k Welded - With the Angels Now so that I don't have to be.
Long Live the Garage Queen !
96 Medium Willow Green Metallic 103k Resurrected, Welded, Eaton M90 inside
96 Rosemist 72k 2006 Best Of SHO, Popular Vote, 2007 Best Gen 3, Welded
96 Medium Graphite 120k - Resurrected, Welded
97 Pacific Green - Parting this one Out
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That IS the flow rate of the 98, AFTER changing the filter and fluid.
Changing the fluid in 2 cars back to back allowed me a direct comparison of
flow rates between them.

I put in new MerconV, and a bottle of Lucas. I did this Friday afternoon,
then drove the car Friday night a short distance and it felt normal. I
drove it Sat. to run some errands and it felt normal. These were all short
trips, and the car felt the same as it did before the fluid change. I drove
it 20 miles round trip to church this morning and it still felt OK, locking
the TC like it should and leaving it locked most of the time. I decided to
drive a little farther as a test so I did another 20 miles on the freeways
around home. Near the end of that time the TC started locking/unlocking
frequently as it had been doing before.

The slow flow rate told me that irregardless of how the trans. works I
probably need to replace the pump. I was surprised that the thing worked at
all. So, that is the next thing I have to do.

bj
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Apply for a home equity line of credit??? ;)

SHOGRL
Car #1 at 2008 Seattle Convention
'95 ATX Deep Emerald Green with half/half mocha interior at 128K miles
Tokico struts
26 mm swaybar
96 brake upgrade
"The Mean Green Stealth Machine
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Our house needs a new roof, my wife wants new floors in part of the house, plus a remodel of the master bath. So if we did the home equity thing that money would instantly be spoken for.

What I'll have to do is take a day off of work and pull the end cover off of the trans. myself.
bj
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Are you sure it's the pump and not something in the cooler lines? I'd
probable chuck the factory steel lines in favor of a couple barbed hose
fittings and tranny line hose first, just to be sure (and if you've
already done that, double check that you don't have a kink somewhere.
I've also seen factory cooler lines pinched between the body and
subframe that would also cause this.). With that kind of flow, I have a
hard time believing the pump is at fault as it doesn't look like enough
volume or pressure to operate the clutch packs/bands/TQ converter.

FWIW, the weird torque converter behavior could be due to the tranny
overheating. This would also fit with that poor flow to the cooler
assembly. Coincidence?

Worth a look?
Dave Garber
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You know what, you're right - Pinched tranny lines.

Something like this was on Daniel Holtman's car IIRC, but his
manifested itself in a weird location Leak IIRC.

On this case, no mention was made of a engine swap.

Was there one?
Eric Lehmann
97 Ebony 42k Welded - With the Angels Now so that I don't have to be.
Long Live the Garage Queen !
96 Medium Willow Green Metallic 103k Resurrected, Welded, Eaton M90 inside
96 Rosemist 72k 2006 Best Of SHO, Popular Vote, 2007 Best Gen 3, Welded
96 Medium Graphite 120k - Resurrected, Welded
97 Pacific Green - Parting this one Out
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I've never even traced the factory lines but I'll try that before I saw off
the left fender and bust into the trans.

bj
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+1. That was my first thought, too

Dan Carman
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Yeah, those OE cooler lines have a tendency to get pinched between the body and subframe on the driver's side right by the front subframe bushing. I didn't notice the pinched line on mine until I started dump tranny fluid all over the ground and the line was nearly cut in half.
Daniel Holtman
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That is one of the many reasons I don't have any OE cooler lines in my car. I didn't like the way they were positioned, I had several "modifications" to the trans cooling system, and standard 3/8" flexible lines seem to have better flow capability anyway. The only trick is making sure to route the flex lines so they don't have any sharp bends, but overall the swap was painless.
Dan Carman
Philadelphia, PA
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Is that side the return side?

My understanding is that the fluid flows to the passenger side, then through that end of the radiator, then enters the passenger side end of the factory cooler, comes out the driver side end of the cooler, and then returns to the trans.

If I have a restriction it would have to be between the trans. and the passenger side end of the factory cooler.
bj
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Both sides run right by there.
Daniel Holtman


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