Trans oil leak 924S 1987

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nagykurva
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Hello Pokes!

New issue on the 924s 1987 !
after some spirited mountain driving in October I started to hear some noises with shifting. Heaviest when I release the throttle in 2nd & 3rd gear(a sort of metal rattle?) . I did the usual net searches and tried to follow the Clarkes troubleshooting. I thought it may be the CVs so took them off- they apparently are 911s (previous owner placed). So I bit the bullet and just replaced both as they also seemed damaged and probably needed to go. At the time I saw a small amount of fluid at the rear of the transmission. I wiped it off just to see if it would come back.
The shifting problems continued. down shifting 3rd to 2nd became more and more difficult.
Before I took to have it seen I decided to change to transmission fluid. I had changed the trans fluid <1year ago but I put a different type of fluid than the Red Line some recommended. I forgot to check how low the level was before draining :( , but didn't see metal shavings and fluid looked normal in color from what I could tell.
I did see fluid in the same pattern though as seen in the pics...

could it be coming from the trans case lid? it almost seems like it starts there...
I don't any feel any fluid on the superior aspect of the trans..

any help suggestions appreciated....

Kevin
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Evan
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That leak is almost certainly the rear transmission seal. It's a common issue. The oil slings out from the rotating flange and coats everything, matching your photos exactly.
Your shifting problems and noise point to low fluid from the leak. The symptoms suggest internal bearing wear from lack of lubrication.

Check the fluid level on level ground with the engine off. If it's low, top it up with the correct GL-4 fluid.
The fix is to replace the rear seal and flange o-ring. If the problems continue after that, the internal damage is likely already done from running low on oil.

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nagykurva
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Evan thanks,
yes after refilling the gear oil I ran it for 60min and seems like most of the issues went away...
When you mean the rear seal - I presume you mean #12?
I'm not sure what is the "O ring" ?

also can this be done with the trans on the car? or must it be taken down?
thanks again
Kevin
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Rich323ard
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Get a reseal kit for $70 and replace all of the seals if you're going to take the transmission down anyway. You can drop the transmission in your garage with some jacks stands and a cheap transmission jackstand fron harbor freight. Just follow the steps.

With youtube, all things are possible.

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nagykurva
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thanks!
I bought the kit and end seal... I've taken the trans off before (with the HF trans jack!) ... I guess I was just getting lazy - but will have to get to it soon.!
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