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Old 05-28-2002, 04:19 AM
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1980 Auto Trans. (Is it different from the rest ?)

I picked up a filter kit for the tranny today and got chatting to the guy at the parts counter. He said the 1980 was a one-off year when it came to transmissions.And he told me the vacuum was set up differently.
Apparently the owner of this parts place has a 1980 and he's tried all sorts of things. He's replaced all the vacuum bits and had a few 2nd opinions and they all seem to agree that 1980 was strange.
Be that as it may I changed my filter today and put in Quaker State semi-synthetic.( They only had two litres of straight synth left or I would have gone that route.)
I pulled out of my driveway and went cruising after I finished.
Instant difference. It shifted the way my wife's car shifts (a 1982).

For the first time it downshifted immediately when I threw the shifter to " S ".
Upshifts were smooth with no flaring.
Kickdown worked correctly.

That was for the first ten minutes.
Then the flaring began again.
I pulled back into the driveway again and saw that I was leaking ATF from the pan. I'd had a funny feeling as I was putting the pan back on; that the gasket ( which seemed slightly undersized as I stretched it over the rim) had slipped out of place as I pushed the pan into position. Yup . . . that'd be it !
I sure wasn't happy about crawling underneath there again, especially since it was now raining.
Pushed the gasket back into place ( more maleable now) and zipped it all up again.
And another test drive. Took it for a long spin this time and once again the symptons worsened the longer I drove. Took it out on the highway and burned up and down a bit. It was definitely better (perhaps 30% ? ) than before the new filter and fluid but I know there's still something very wrong.

Coupla Questions ! ?

Just what exactly happens when you're a quart over on fluid ?
I was over my first trip out of the driveway (misread the quantity in the Haynes :-> ) but didn't sense anything too amiss.
And . .
Why does it shift perfectly sometimes and not others ?

I think this tranny business is a big issue for owners of older diesels and from the searching I've done, it doesn't appear that anyone has yet put together the perfect guide. Though many seem to have come close.


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Old 05-31-2002, 02:05 AM
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I have a new question on this tranny.
After reading more and getting more confused I think I might have the answer.
The vacuum line leading from the Bleed valve on the Ignition pump to the modulator on the transmission isn't hard plastic like the other lines but kind of a soft black rubber. It isn't blocked when I blow through it and yet I'm wondering if perhaps as the car heats up, it softens and collapses.
My tranny, I now know, would be described by the cognoscenti as a 722.118.
Any takers on this one ?

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Old 05-31-2002, 12:32 PM
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As always, thanks Bill for coming through again.
I had a feeling that line wasn't correct.
I'll feed a new line in today and keep my fingers crossed.

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Old 06-01-2002, 04:53 AM
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My apologies for monopolizing this thread.
Oh well . .
I'm like that. !

As I couldn't find any plastic vacuum hose at my local Lordco Parts or Canadian Tire, I decided to swap out the "O" ring on the transmission modulator as another poster (I forget who ?)said, it was probably the only part likely to fail on the modulator.

This also gives me the opportunity to try posting a picture here,
It should be useful to anyone dealing with an unfamiliar tranny and could be used perhaps on the burgeoning FAQ page which is a very exciting developement here.

So here goes.

Hope it works.
Attached Thumbnails
1980 Auto Trans. (Is it different from the rest ?)-modulator.jpg  

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