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Umm tranny #'s

Kats66Pny

Active Member
Ok so I was looking at all the numbers on the trans so I could try to make sure what I have is a C4, year, yada yada yada.....

On the one side that said Ford (with a circle around it) had the numbers D50P-7006-AA ..at least I think that's the numbers. Hard to tell the difference between the zero and o's sometimes.

Googling that number I found something that says it's from a 1975 something? :shrug

Oh and got to love JohnPro. Not here anymore, but still helping answer some of my questions.. like the bolts! :thu
http://forums.vintage-mustang.com/vinta ... ssion.html
 
That definitely sounds like a '75 tranny. The '70 tranny has a larger input shaft than the earlier versions. The '70 trans is more desirable for beefing up.

I just had an earlier one (a '67) and a later version (a '70) sitting on the shop floor. I'll try and recall the differences in them -- Does the dipstick go into the case or the pan. The early c4's that I have the dipstick goes into the case, and the '70 c4 has the dipstick going into the pan. Also, I think the early c4's have a vent tube on the side of the trans and the 70 has a vent on the top. IIRC, the bellhousing bolts on the early version also holds on the front pump, so if you take off the bellhousing, the front pump has a tendency to come off. The later style the pump is bolted separately.

If you would have asked a couple of days ago, I could have taken pictures of them side-by-side. But I've already installed one and put the other under the bench.
 
Dipstick goes into the pan. - Pay no attention to the bent up lines. Those were a PO thing when he did the trans cooler. They are being replaced and the lines done correctly so they aren't just hanging under the car.

IMG_4674.jpg

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and while I'm looking over the trans... where in the hell does the speedo cable hook up at?
 
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That looks exactly like my '70 C4 that i just installed on Moostang's 65 coupe (except mine is clean and painted black :roll ). Looking at the pictures, that's an interesting servo cover on the passenger side. Is that just some flat steel that's bolted to the case? I wonder what's under that. Most servo covers have a marking on them -- a large letter, typically an A, C, or H. There's also R and Z that I've seen. And the aftermarket servos I've seen are made from billet aluminum. interesting.

Are you gonna stay with the B&M (or other aftermarket) shifter or go back to stock? Being a former race car (or wanna be race car) do this have a manual valve body? There's no kickdown lever.

The speedo cable is on the drivers side on the tail shaft. It's right behind the crossmember in that last pic. It appears that a Vehicle Speed Sensor (VSS) is bolt in where the speedo cable goes. If that is a vss, you could easily install an electric speedometer.

Nice hard lines!! Before switching over to the tko, I got tired of dealing with the hard metal lines. When I parted out my old 66 coupe and put that tranny into my fastback, it just used rubber fuel lines to run to the cooler. I never had any problem running the rubber lines. I just made sure not to run them too close to the headers.
 
Looking at the pictures, that's an interesting servo cover on the passenger side. Is that just some flat steel that's bolted to the case? I wonder what's under that. Most servo covers have a marking on them -- a large letter, typically an A, C, or H. There's also R and Z that I've seen. And the aftermarket servos I've seen are made from billet aluminum. interesting.
I don't know wtf a servo is. LOL but yeah, it's just a piece of metal bolts on, but it feels smooth like it was cut specifically for it. :shrug

Are you gonna stay with the B&M (or other aftermarket) shifter or go back to stock? Being a former race car (or wanna be race car) do this have a manual valve body? There's no kickdown lever.
I'm still undecided about shifters. I like the B&M one I have. It does (makes driving fun.. still have to manually shift but no clutch and that's awesome because I don't know how to drive manual. :hide In some ways I like the idea of a stock shifter so I can get a console that will actually fit (makes my life easier). As is, the B&M was moved back, almost between the two front seats which is going to make finding a console hard and I'll have to actually make a custom one, which I wouldn't mind. It does leave more room moved back where it is to put cup holders or something. :thu

The speedo cable is on the drivers side on the tail shaft. It's right behind the crossmember in that last pic. It appears that a Vehicle Speed Sensor (VSS) is bolt in where the speedo cable goes. If that is a vss, you could easily install an electric speedometer.

Ok I gotcha. That thing poking out. I don't know whats in there, but I do know Gertrude had no speedometer, no cable... only a tach, and if I put in my 66 dash cluster I've been waiting to install... I'm going to have to hook up a speedo cable.
 
"Kats66Pny" said:
I don't know wtf a servo is. LOL but yeah, it's just a piece of metal bolts on, but it feels smooth like it was cut specifically for it. :shrug

Ok I gotcha. That thing poking out. I don't know whats in there, but I do know Gertrude had no speedometer, no cable... only a tach, and if I put in my 66 dash cluster I've been waiting to install... I'm going to have to hook up a speedo cable.

Ok...I'm not all that knowledgeable about the servos, so here goes nothing. Behind that plate is the intermeidate servo, which is attached to the intermediate band. That band will affect how your tranny shifts. There are a bunch of different servo letters that I mentioned earlier. And basically the servo is a piston. The servos are different sizes, and that determines how well the band holds. In the tranny I just installed in the wife's car, it has the R servo, which is the most desirable for drag racing and nice crisp shifts. When I had that trans in my fastback behind my radical 351W, down at the track when I'd get on it, the shifts were nice and tight. Damn near give you whiplash. The next best is the C servo, and then the H servos are very popular, both have good holding pressure. One of the more common is the A. That's what most production cars came with. Stay away from the Z servo. Those came on the 4 and 6 cylinder cars. If you're not gonna be drag racing, most any servo will work -- just stay away from the Z servo.

As I was typing this I remembered I have a Z servo that I yanked out of a trans that was given to the wife when she bought her car. If you notice the servo fits inside the cover, so I just don't understand what the metal plate function is and what's behind it. hmmmmmm.....

Since you have the trans out, are you gonna take it apart and see how all the bands and clutches are? Are is the trans pretty fresh?

Yep that thing sticking out is the VSS. If you remove the VSS its just held in by one bolt, 7/16" head. There should be a gear on the end. If you look inside the case, you should be able to see the drive gear. At this point, if you have the budget, you might want to look into an autometer electric speedo. Very easy to wire. I love the one I have in my car. I don't know how may speedo cables I've melted over the years, cause of the exhaust!!
 

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Ok...I'm not all that knowledgeable about the servos, so here goes nothing. Behind that plate is the intermeidate servo, which is attached to the intermediate band. That band will affect how your tranny shifts.

:confu Does that affect how my B&M ratchet shift works? Because I don't know if it was PO didn't install the shifter correctly or purposely did it this way... but the B&M Quicksilver is suppose to have two functions ... ratchet mode and straight gate mode so you can drive it like a normal auto and not have to shift gears, but mine doesn't work. It only works in ratchet mode. I know the PO was building the car to drag race in, and so I can only guess that whatever servo thing that's on there, was one good for racing. :shrug

I looked and cleaned that metal piece to see if anything was hiding under the dirt... nothing. No letters, numbers, nada. Smooth shiny piece of metal. Would anything bad happen if I take it off? lol I'm curious if maybe there's a letter on the inside.

Since you have the trans out, are you gonna take it apart and see how all the bands and clutches are? Are is the trans pretty fresh?

Take apart a transmission... hmm. I don't know if I have the skills for that. LOL Supposedly the trans was rebuilt... but when exactly.. who knows. I didn't have any problems with it, other than not being able to put my shifter in normal auto mode.
 
"Kats66Pny" said:
If that is the case... then would I just replace it with something like this?

http://www.summitracing.com/parts/TCI-522100/

That had been my plan with my old C4 before I found one that already had the extra clutch, shift kit, higher stall etc, etc already installed. One of these days I am going to go for the AOD conversion myself.

Your dipstick goes through the pan so it's def different then mine but looking at it it's also definitely a C4. They made those things for many years with only slight changes through the years.
 
That would work. You need to know what you have before doing anything. You may be able to see what you have by pulling the pan and looking at the valve body for any markings.
 
One of these days I am going to go for the AOD conversion myself.

I might go the AOD route one day. My husband keeps talking about it, but I see no reason to do it right away when the trans I have works just fine.


That would work. You need to know what you have before doing anything. You may be able to see what you have by pulling the pan and looking at the valve body for any markings.

Sounds simple enough. :thu
 
If you have to shift manually, then I guess it goes without saying that you have a manual valve body in it. Now, is it a forward (PRN321) or a reverse (PRN123) manual valve body? It might be tough to look at the valve body to tell. The reverse manual valve body that I have looks exactly like the normal one...IIRC, it's just a stock ford valve body that someone worked over. That one from summit would work. Replacing a valve body is pretty easy. Just need to yank the pan, and unbolt it. Then bolt the new one in. Just make sure that you have the shift lever and kickdown levers in place or it won't bolt down. It looks like you'd need to get a kickdown lever. I didn't see it in the pics.

"Kats66Pny" said:
I looked and cleaned that metal piece to see if anything was hiding under the dirt... nothing. No letters, numbers, nada. Smooth shiny piece of metal. Would anything bad happen if I take it off? lol I'm curious if maybe there's a letter on the inside.

Take apart a transmission... hmm. I don't know if I have the skills for that. LOL Supposedly the trans was rebuilt... but when exactly.. who knows. I didn't have any problems with it, other than not being able to put my shifter in normal auto mode.

Careful taking it off. There's a massive spring on the backside of the servo. On the opposite side of that cover is the intermediate band adjustment. And attached to the servo and adjustments are some "struts" that would fall down inside the case. Then you'd have to take the pan, and valvebody off to fish the pieces out and reinstall them. Here's a diagram of the band and if you notice parts 7D029 are smaller parts and have a tendency to drop down. Here's a pic I found that shows what the band and struts look like: Intermediate band. that pic is from this writeup on rebuilding the c4

"Kats66Pny" said:
Take apart a transmission... hmm. I don't know if I have the skills for that. LOL Supposedly the trans was rebuilt... but when exactly.. who knows. I didn't have any problems with it, other than not being able to put my shifter in normal auto mode.

If I can do it, anyone can. I went out and bought the Haynes manual for rebuilding ford autos. It has step by step pictures on the rebuilding process. And there's alot of good videos out there. So, far I've rebuilt two, and they both worked! The worst part is the mess of tranny fluid goes everywhere.
 
Ok I took the pan off. Is the valve body that larger metal piece or underneath there?
IMG_4678.jpg



There's also some identification on the one piece.
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Careful taking it off. There's a massive spring on the backside of the servo. On the opposite side of that cover is the intermediate band adjustment. And attached to the servo and adjustments are some "struts" that would fall down inside the case. Then you'd have to take the pan, and valvebody off to fish the pieces out and reinstall them. Here's a diagram of the band and if you notice parts 7D029 are smaller parts and have a tendency to drop down. Here's a pic I found that shows what the band and struts look like: Intermediate band. that pic is from this writeup on rebuilding the c4

Awesome! Thanks! :yah Pictures are always good to look at!
 
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"Kats66Pny" said:
Ok I took the pan off. Is the valve body that larger metal piece or underneath there?
IMG_4678.jpg


There's also some identification on the one piece.
IMG_4679-1.jpg


Awesome! Thanks! :yah Pictures are always good to look at!

Yep. That's the bottom part of the valve body. The valve body is made up of three pieces: top, bottom and a middle plate -- and a couple of gaskets between them. It's not tough to remove a valve body. When putting it back in, you just have to make sure that the levers, and valves are lined up.

Well, that's a ford valve body from a '72. Those '70+ c4's are what you want. They have a bigger input shaft (now that just don't sound right!!) and there's more modifications that can be done to 'em -- shift kits, valve bodies, trans brakes...
 
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Ford part numbers are pretty easy to decode. On the valve body it states RF-D2AP-7Z101-AA: I'm not sure what the RF stands for, but the rest is easy: D is the decade: C=60's, D=70's, E=80's...etc. so D2 means it a '72 part. and so forth. Here's a good website that goes into much more detail: http://www.mustangtek.com/FordDecode.html Or just google "decoding ford part numbers" and you will get more information that what you really wanted!!! =^)
 
Kat
If you end up buying a new valve body, let me know what you want for the manual one. It would be used in the Drag car I'm building.
Thanks
 
If it turns out to be a manual, and I have to swap it... it's all yours. :thu

Someone on another forum said "Just a guess from the pic since it has a vacuum modulator I would think automatic valve body." :confu
 
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