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Discussion Starter #21
cool Greg, i hope it was for upgrades anyhow the box is back in the car with your band settings and is better but unfortunately the squeal is still there. your pressure numbers are close to that of the transgo kit i believe whereas mine are 150 in forward gears and 280 in reverse down from 320. this is baffling everybody and frustrating me no end so what do think about installing a dedicated manual valve body or is there something more i can do to this valve body (steel balls, softer/harder springs, enlarged holes etc)?
 

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Wow , is it really the trans causing the squeal? Very unusual.. That kit usually is ok..Not really a lot else you can change..

I have used quite a few valvebodies from PTC in Melbourne . They convert yours to forward manual i guess would be the next step forward.
It is different to the transgo kit , Their mods convert to a fixed line pressure so does away with the modulator
 

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Discussion Starter #23
funny you say that because when i drove it yesterday the box squealed in 3rd with no gear change just on the accelerator from about 3000 rpm and i backed off. converter is the same one that i had when i built this 3 builds ago when this sound started and would not have done more than 150-200 km since. my opinion is that it is the box for one reason, the burnt parts that come out of it such as the forward clutches and high clutch were burnt when it squealed in 1st 2nd and 3rd with no band discoloration, forward clutch fixed and squealed in 2nd to 3rd change and burnt the high clutch and rear band drum. could be i am wrong, what do you think?
 

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Discussion Starter #24
hello again Greg, i may have a solution. while looking up ptc i found a thread on xfalcon from 2011 where you put up a picture and sizes of the holes drilled in the seperator plate C4 build Q's - Page 2 - Transmission/Driveline - xFalcon.com - X-Series Falcon Owners Club which has holes bigger than those drilled in mine with the transgo supplied drill bit. could this be the problem and if not would this be worth trying?
keep the great work rolling.
 

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I think you're right , burnt parts are not good .. I'm curious why the forwards would burn . If the line pressure is good , the forwards never do any work . Mostly they come out looking new .
That pic is actually one of my own valvebodies . It was an experiment I did for auto shifts behind a stroker big block..

The transgo drill is .110" That is usually plenty. I have done some to .125" but in your case all that will really do is firm the 2-3 shift.

The other hole that is drilled that transgo don't drill is a feed for the 2-3 shift valve through the 2-3 backout valve. But in that case I have blocked the 2-3 backout totally
The transgo kit that is still functional

I'm running out of ideas :(
I take it line pressure as you say is ok? Have you driven with a pressure gauge on it ? Does it have good line pressure rise as you accelerate and vacuum drops ? The modulator and valve and pin are all functional? Good vacuum ?
Even at idle , check pressure , then disconnect the vacuum totally, line pressure should jump up ?

The 1-2 + 2-3 shifts feel ok normal driving ?
 

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Discussion Starter #26
mmm so could this small hole 110" be a restriction causing less apply pressure letting the engine drive over the top of the clutches? which was my thought when i found that picture.
i havent driven it with the gauge this time and will do tomorrow, and when on the stands it went 280 reverse 150 without changing in all 3 forward gear from idle to 3500 rpm
the modulator is 3 full turns in with an extra long pin giving 2.5mm preload
vacuum is about 8 inches at idle
will check vacuum and line pressure again with modulator disconnected
the shifts feel good with normal driving, a little quicker and firmer than stock.
your help is immeasurable, so please dont stop the ideas coming
 

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Hmmm Hard to pick the sound there . Sounds to be shifting ok .
Looks like 150ish psi max? And does have line rise with vacuum drop. Did the pressure go any higher with vacuum disconnected ?
 

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Discussion Starter #30
hi Greg, i wasn't sure how well it would come through so thats ok. yes 150 max on the green spring and i couldn't get the, no vacuum test done. its all still set up for another run tomorrow and will post the results. can i drill those holes larger than 110" or is there a bigger problem?
 

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You could try a bit bigger , As per pic . .125" is fairly common size in a lot of kits. Drilling from .110-.125" does give a 30% flow increase. I have tried in the past and there is a difference even though it seems a small change . We're running out of ideas otherwise. Usually not necessary but it might just help ?
 

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Hmmmm , can def hear it there now . Pressure still about same max.... Hard to pick what it is. Trying to think outside the square now

So the valvebody is done exactly as per the Transgo 40-3 Manual kit??
Correct Transgo gasket used ??
What pan and filter ? Dipstick verified correct oil level.

The pressure reg valve is all free when valvebody was done ?
The valve and spring under the filter tab fitted correctly ?
 

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Discussion Starter #36
thank you for sticking with it, and for the info for the separator plate which i will try.
transgo kit as per the instructions and correct gasket used. this is a pan fill and has correct level, deep b&m pan with there filter extension and 904 filter.
all valves were removed cleaned and checked for ease of movement with 2 being sticky cutback valve and the one next to the pressure regulator.
yes valve into body the correct direction with the spring under the filter.
questions that come to mind are, how the pressure changes when all the parts stay the same and why is reverse so high and forward pressure is low?
while i was driving i brought the rpm up to about 4k in 1st slowly then got on it which lost traction so i short shifted, the box held on with a sharp shift not solid and no sound. that was on a long driveway which is clean and abrasive (bitumen not concrete) and pulled harder than it ever has while spinning and if i am just cruising and accelerate it squeals which i don't understand. this is more than unusual and your help is very much appreciated
 

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Discussion Starter #39
sorry its a dacron and i take it i can buy a brass screen and it would be better for catching debris and also flow more?
 

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sorry its a dacron and i take it i can buy a brass screen and it would be better for catching debris and also flow more?
The Dacron actually have better filtering, but sometimes Ford trannys don't like them.

The screen type is all Ford used back then.
Screen types flow better but don't filter as good.

I had a C6 that I put a Dacron filter on, and the Pressure Reg valve would buzz/complain when it was cold.
Seemed ok warm but I went back to the screen type.

I also toss a strong magnet in the pan to catch debris.

I don't remember which tranny it was for, but Trans-go had a kit that warned to NOT use a Dacron filter.
They wanted screen type only.
 
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