trans seals and leaks- I need opinions

slant6billy

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Ok so after many many year I have a spot in the garage and in the driveway. So my 904 in my F-body is temporary anyway, but the other culprit in the pissing party is my van with the 904/998/999 variant. My thought is to rip open my 904 and learn off it- who cares. The van is the vifes and I can't screw up or screw around with taking too long on that one. What is feeling here on leaving a leaky trans in? Anyone have issues with changing the front seal? I know my dad's 83 5th Ave used to leak for almost 20 years and shifted great in forward but slammed in reverse when it could find it. Until I put the clutchflite in the F body, it is going to dirty the garage, but it could be a good opportunity to "learn trans rebuilding" for when it counts. Funny how these front seals leak after fluid changes...... What's in that ATF mopar fluid anyway?
 

MiradaMegacab

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While we are on the subject of trans leaks, if the car sits for an extended period of time the converter drains. This fills the trans and will sometimes leak from where the fill tube plugs into the trans case. A new o-ring and some RTV will be the fix for this condition.
 

slant6billy

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Yep, the fill tube o ring is sloppy wet. Speedo connection too, but nothing out the tail. The small slot in the dust cover by the torqueconverter is weeping too- front seal. I also suspect the new ATF 4 and now ATF 5 is way too nasty for older trans with older seals and materials. Just like the filler material in gasoline lately has really affected my tuning on everything from my weedwacker & lawnmower to the injected stuff.
RTV away..... I got tubes everywhere..... thanks
 

ramenth

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Wanna get into trans work and use what you've got as a test mule? Get a good book and learn what everything is that's in there as you take it apart. Be patient, don't pry on anything (there's hidden snap rings), and take it apart carefully. If you have a good camera take pics of everything of how it looks in the case and how it looks laying on the bench.

Same way with the valve body. Take off one piece at a time and take pics. There's balls in there that need to go in the right spot.

As for ATF4, I use it in just about all my Mopars. Everyone of my Chrysler customers who gets a trans overhaul leaves the shop with it in his or her trans. If I have a question of what they've been using on older stuff, I'll flush everything and put ATF4 in it. Take a look at Chrysler's TSB's and it retrofits all the way back to 7176 (remember, Dex/Merc was compatible for top off, not for complete fills). It's not the oil, it's the seals, if you're experiencing leaks. They'd leak eventually, no matter what oil you use in there.
 

Jack Meoff

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(remember, Dex/Merc was compatible for top off, not for complete fills).[/QUOTE]

If I'm doing a complete fluid change what should I be filling my 87 5th with?
 

slant6billy

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Now, what about "snake oils"? Royal Purple? Z Max, Barqs, trans cool adder, etc. I had a firechicken GTA for about a month and a half- wetter water froze the rad. waterpump flush ate the aluminum bypass. B&M quikshift ate the 700R4. Synth gear oil grenaded the rearend. My dad shook his head and drove off in his 83 5th ave.
So I don't trust "adders" What do you all think? Other than my dad being right!
 

Erics5th

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The B&M Quick Shift is just Type F transmission fluid (with a different die) designed for Ford. Type F actually works well in Torqueflites. Guess not in GM tranny's!
 

Jack Meoff

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I had a POS 89 Caprice as a beater and the tranny was on it's way out
I tried that Lucas transmission fix crap.
Did a great job of turning my fluid into soup.
Did jack for the tranny.
When I was doing body work on my Caravelle the guy letting me use his shop restored his own cars and trucks. An absolute master and very crusty and set in his ways
(Which were usually right).
I asked him once if I should start using synthetic oil in the slant
He gave me a scowl and said...
"That things been running 10-30 since the day it was made..
Don't go screwing with it now!"
He never liked any "additive crap" as he would put it.
I ain't big on 'em either.
 

Mroldart2u

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I asked him once if I should start using synthetic oil in the slant
He gave me a scowl and said...
"That things been running 10-30 since the day it was made..
Don't go screwing with it now!"
He never liked any "additive crap" as he would put it.
I ain't big on 'em either.

I concur, I have never been a fan of "Synthetic" anything... Whats wrong with the "Real" stuff.... Only nightmarish stories have i heard from "switching" stuff around... M2C
 

slant6billy

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Actually, after I posted, a co-worker reminded me that I put a quart of B&M in the F body. I guess I forgot that. Probably figured it did not matter since the old 904 is getting replaced anyway. I put in the B&M stuff in because I noticed the launch was weak. Or was weaker than usual. So now it pulls the front end up like it did before.
I have to agree with using 10W30 Valvoline in the mopars with only the exception being the SS/T. It has had Mobil1 full synth since 9000 miles and it is clean on the inside as clean on the out.
 

MiradaMegacab

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I use type F in my racing 727.

I took out the torque conv clutch plate in a 904 by running Dex3. Upon lockup there was alot of chatter.

Street driven stock Mopar trans gets ATF 4.
 

ramenth

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I concur, I have never been a fan of "Synthetic" anything... Whats wrong with the "Real" stuff.... Only nightmarish stories have i heard from "switching" stuff around... M2C

The thing of it is, synthetic is "real." It's just a further step in the refining process.

In the topic at hand, though, it's a matter of what refined base oil is being used and what has been added to the process to work within the given parameters of the design.

All transmission fluids are "synthetic" to a certain degree. All of 'em have pretty much started off as a given further refined base oil and all have certain additives that have been used for the parameters of the transmission.

Just saying.
 
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