[ronzoni]

Just some words to the wise from a knuckle head who just rebuilt a C4 for the first time. Start with a clean, well organized workbench, and then don't be in a hurry. Keep the stuff in the order it comes out too. The service manual is an almost "must have", it helps with the clutch pack tolerances as well as the overall endplay values, and how to set with the selective thrust washers.

Question: The clutch pack tolerances are achieved using different sized snap rings, where in the world do you find those?!?!?

Ron.

 

[dark7068]

Talk to the guys at a tranny shop. Most of them here are very helpful, let them know the tolerances and they might be able to help out.

Rick

 

[evilmess]

ronzoni,
What kind of time(hours) do you have into your rebuild?

on a side note...

I was wondering, what's the max HP a C4 can handle?

 

[Cougrrcj]

Transmission power handling capabilities

Trannies really don't care about horsepower. Torque is the limiting factor! Torque is the twisting power the engine has against a resistance. Even then it all depends on what you've done to the transmission.

If you change the pressure, you'll increase the torque handling capacity (within reason). Another big big factor is how well the shift points are timed. If you have a 'runaway' between shifts, you'll fry bands or clutches.

As you noted, the select fit parts will also determing how well the clutches hold.

There are all sorts of tricks that one can learn to make your trans 'bulletproof'. Ask around. You might be surprised!

 

[clevelandcougar]

I am also going to attempt the do it yourself C4 rebuild. Do you need any special tools? Such as dial calipers or other special measuring tools.

 

[ronzoni]

special tools

I can think of a few;

Snap ring pliers
dial caliper (helpful but maybe not necessary)
Feeler gauges
dial indicator( for overall endplay measurement)
My dial indicator is on a magnetic base that I attached right to the stationary pump shaft, the big splined shaft the torque converter slides onto. You'll need some small picks or screwdrivers to get out the various bigger snap rings too.

Invest the $32 in the thrust washer kit, it'll help your endplay value out a lot, plus you don't want your tranny to go quickly for want of $32 worth of parts.

Soak up the friction bands in some fresh fluid overnight before measuring your clutch pack tolerances. They swell a lot.

If you can, lay your hands on the service manual that is on ebay from time to time, I did mine without, until the home stretch when I finally consulted the book, and it was VERY helpful. Start with it and you'll be glad you did. I had perhaps 10 hours in on mine, but I messed around with it (learning curve you know)

Ron.

 

[krugar67]

C4 fluid

I was told by a reputable tranny guy that if you are not installing a Ford trans rebuild kit you need to run dexron and NOT type F.He said that the friction material was different than the stuff uses on the discs.

Has anybody else been told this?I also heard you may run 20-20 motor oil,but I don't like the sound of that practice.....too rebellious.

I also needed to find thicker snap rings and I called all the trans guys in the area and the usual reply was,"Huh?Just put an extra disc in it."

I don't think so.

So I took an old clutch plate and had it ground down to act as a shim between the original snap ring and the clutch plate.Works good.(I hope)

 

[bruter]

Speaking of shift points...is there any way of knowing if a PO put in a shift kit. My C4 has nice crisp shifts and I suspect the tranny may have been modified? I'm not complaining about the performance...just curious!:

 

[evilmess]

I was also thinking that adding transmission cooler would make sense regardless of whether you're building a hot rod or stocker. Since the best driving time is in the summer (ie. Hot), a transmission cooler would be the most benificial during this time of year and also on longer road trips.

Am i off base with this idea? :1poke:

 

[ronzoni]

I already put in a trans cooler a couple months ago. My need to rebuild, however, was occasioned due to the failure of a $0.48 snap ring on the output shaft. Ground up a lot of stuff, including the governor. I also am installing an "in line" filter with internal magnet to do a better job of cleaning the oil, the "gravel screen" that is the filter on the C4's is too coarse.

Krugar67, I'd be interested to hear more about how your shimming idea works. Have you run it yet? If so, is it staying in place? I'm concerned about something that is 0.015" thick wanting to come out.

 

[krugar67]

Ronzoni

No I haven't run it yet,but I hope to have it going next year.Being the unsupervised rebuilder of a successful TH400 ,I see no reason why a .015 shim would not hold up in a C4 or any other trans.If you want my trans to be the guinea pig,I'd be more than happy but you'll have to wait about another year before I can test it.

Although a thicker snap ring is the way to go,I've yet to find anyone who can supply them.I've spent many hours on the internet searching for them to no avail,and my local dealers claim they are obsolete.

Sure it's frustrating....but that's how sites and clubs like this arise,not to mention my dependancy on prozac.

Keep the faith.

 

[calcat]

Just FYI guys but www.fordmuscle.com has a whole forum dedicated to rebuilding the C-4. good info on where to find selective snap rings.

 

[ronzoni]

I HAVE SEEN THE LIGHT!!!!

Thank you for the lead Calcat, the Ford Muscle website has some great/ absolutely necessary info for C4 builders that are running big power. (500 hp+, up to 1200hp through a C4!!)

There are 8 pages on the C4 Forum! Over 100 Posts!

The selective snap rings and the selective thrust washers #1 and #2 can be bought from:

Transtar
(314)647-7203 Ask for Ken.

This is the St Louis regional branch; their main place wasn't aware of these parts, nor were the two other parts guys at the St Louis location.

SEE! They have them and don't even know it!! Some people have just stopped trying, however in their defense, no one uses them or cares about them anymore. All of the tranny shops say "I just put those old ones together and don't worry about tolerances" OK for the little old lady from pasadena, but not me.

Some other tips:
It is critically important to get the overall endplay and clutch pack tolerances RIGHT to make the little C4's live.

The "H" servo is the best, without going to an aftermarket unit.

The substitution of roller bearings for bronze thrust washers takes $$, unless you can machine your own races. It's not necessary, according to Gerald @ Performance Automatics, until around the 800 HP point.

 

[b0nes421]

Has anyone tried that Dexron Mercon III?

A guy at a local shop told me that this stuff was good to go, but I'm not too sure. I thought that Dexron was for Chevy' and such? He told me that the Mercon signified it's use for Ford's and MERCury (Mercon). Not too sure about this one, would like some input.