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Topic: Silicon on Tranny Pan (84 Cougar, C4) (Read 4055 times) previous topic - next topic

Silicon on Tranny Pan (84 Cougar, C4)

I grew up using only gaskets.  Industry has moved on to using silicone
on tranny pans.  Have a C4 which continues to leak periodically at the
gasket and considering going with silicone.

Any comments appreciated re. silicone use on an older tranny.

Silicon on Tranny Pan (84 Cougar, C4)

Reply #1
I've used Permatex before with no issues, but you need to check your pan. It may be bent if have have a reoccurring problem. A replacement pan may be in order, or, if you find that it's bent, you maybe be able to straighten it. Check it with a straight edge. Otherwise, a new gasket with a little bead of the Permatex on each side of the gasket......It has worked for me in the past. I can't say it will for sure with yours..
'88 Sport--T-5,MGW shifter,Trick Flow R intake,Ed Curtis cam,Trick Flow heads,Scorpion rockers,75mm Accufab t-body,3G,mini starter,Taurus fan,BBK long tube headers,O/R H-Pipe, Flowamaster Super 44's, deep and deeper Cobra R wheels, Mass Air and 24's,8.8 with 3.73's,140 mph speedo,Mach 1 chin spoiler,SN-95 springs,CHE control arms,aluminum drive shaft and a lot more..

Silicon on Tranny Pan (84 Cougar, C4)

Reply #2
Thanks for input vinnietbird

Could be bent pan?  Gasket works for the most part, just bolts are either loosening up or gasket is shrinking
enough to cause small leakage as have to periodically retorque pan bolts.
Never considered Permatex. 

My primary concerns with silicon are:
1)  breaking loose and getting in value body.  Since now used by dealers assume this is a false concern.
2)  difficulty of getting pan off.
3)  getting the silicone off tranny after dropping pan. 
    This is of major concern as have yet to find
    anything that will remove it easily.  Did come across a rubber wheel with tits that
    supposedly works -  but how to keep rubber particles from being thrown into the tranny
    while using it is another concern.  They also make a "gel" but you need to leave on for
    couple hours and not sure how this works with gravity.  Also ammonium may work
    (again if you can soak part).    Did the differential housing cover about year ago, had RTV
    and was a "b*&ch" to try and get enough RTV off to get a good seal with the new.

Silicon on Tranny Pan (84 Cougar, C4)

Reply #3
When I redid my C5 trans pan gasket, I believe I used silicone on top of the gasket, but i forgot to bang the pan edges flat again. Apparently they become wavy with bolt torque? I would try just straight high temp/oil "proof" silicone and forget the gasket, unless you find a silicone/rubber type gasket, and not a cork one.

 As far as removing old silicone, any decently sharp ser will take it off a smooth(flat) surface easily.

  Anyway, I got tired of the leaks, so I dumped the auto altogether!

P.S. I recall having leaks form around my band adjustment bolt/nuts, so try siliconing those for sure. Good luck!
1983 Tbird with '03 Split Port V6 motor swap done! Headers, dual exhaust, 500CFM Edelbrock, 3G upgrade, Electric fan. 3.73 Gears and an FRPP Limited Slip. Five lug complete! 5-Speed conversion complete! Standalone Fuel Injection in progress...

Silicon on Tranny Pan (84 Cougar, C4)

Reply #4
They have rubber pan gaskets that have metal grommets in it to prevent over torquing. ...or, as I said...put a little permatex on both sides of the gasket (I spread it on like a thin coating), let the stuff set up for about ten minutes or so, then install it. Removing the pan is easy....Just remove all but a couple of bolts, make sure you have a pan under there, it can get messy, and carefully remove the last two bolts and pull the pan full of fluid off. May as well replace the filter while you're in there as well if it's been a while. If you're not using a torque wrench, snug the bolts down, but obviously not until the pan deforms....You can look around on Ebay and get a thicker d aluminum pan with a drain plug. Those make life really easy for the tranny filter swaps, and usually hold more fluid for better cooling. I've seen good used ones and new ones for a reasonable price..
'88 Sport--T-5,MGW shifter,Trick Flow R intake,Ed Curtis cam,Trick Flow heads,Scorpion rockers,75mm Accufab t-body,3G,mini starter,Taurus fan,BBK long tube headers,O/R H-Pipe, Flowamaster Super 44's, deep and deeper Cobra R wheels, Mass Air and 24's,8.8 with 3.73's,140 mph speedo,Mach 1 chin spoiler,SN-95 springs,CHE control arms,aluminum drive shaft and a lot more..

Silicon on Tranny Pan (84 Cougar, C4)

Reply #5
You could also try a little loc-tite on the bolts, to keep them from loosening.
95 Ranger Splash 2.3
88 Tbird Sport :ies::ies:
5.0 SO, stainless shorty headers, w/ Magnaflow lers. KYB struts, KYB shocks. 5lug conversion from sn95 Mustang, subframe connectors, drilled and slotted rotors, 03 Mach 1 wheels. sequential taillights.140 speedo

Silicon on Tranny Pan (84 Cougar, C4)

Reply #6
x2 for deeper alum pan, mine leaked all the time and I found one of the lips was rolled down slightly. I tried straightening it but it would still drip a little.
88 Turbocoupe: Coast High Performance 331 kit 28oz balance, Comp XE264HR14 cam, 58cc 185 afr heads, 1.7 roller rockers, Mass-Flo EFI (was POS to setup and their techline is a joke at best)
Full 1 5/8 primary equal length headers, 2 1/2 exhaust, Full manual reverse VB c4 and baked off clear coat "BECAUSE RACECAR"

Silicon on Tranny Pan (84 Cougar, C4)

Reply #7
http://cgi.ebay.com/ebaymotors/BTE-FORD-C-4-CASE-FILL-CAST-ALUMINUM-TRANSMISSION-PAN-/250855626942?pt=Motors_Car_Truck_Parts_Accessories&hash=item3a682918be
'88 Sport--T-5,MGW shifter,Trick Flow R intake,Ed Curtis cam,Trick Flow heads,Scorpion rockers,75mm Accufab t-body,3G,mini starter,Taurus fan,BBK long tube headers,O/R H-Pipe, Flowamaster Super 44's, deep and deeper Cobra R wheels, Mass Air and 24's,8.8 with 3.73's,140 mph speedo,Mach 1 chin spoiler,SN-95 springs,CHE control arms,aluminum drive shaft and a lot more..

Silicon on Tranny Pan (84 Cougar, C4)

Reply #8
Thanks all for input. 
vinnietbird appreciate the link.  BTW, I torque everything.

Silicon on Tranny Pan (84 Cougar, C4)

Reply #9
I torque most everything as well.....by feel.LOL.
'88 Sport--T-5,MGW shifter,Trick Flow R intake,Ed Curtis cam,Trick Flow heads,Scorpion rockers,75mm Accufab t-body,3G,mini starter,Taurus fan,BBK long tube headers,O/R H-Pipe, Flowamaster Super 44's, deep and deeper Cobra R wheels, Mass Air and 24's,8.8 with 3.73's,140 mph speedo,Mach 1 chin spoiler,SN-95 springs,CHE control arms,aluminum drive shaft and a lot more..

Silicon on Tranny Pan (84 Cougar, C4)

Reply #10
Using Silicone on basically anything in your tranny or engine is something i never DO. Several reasons. I am detroit diesel certified repair facility along with cummins and mack. Any sign of silicone on the trans or motor voids their warranty. We are also allison certified as well. If one drop of silicone is in that tranny BYE BYE Warranty. Basically Silicone does a poor job of sealing for the most part. we use it in heavy applications that do not get SQUEEZE OUT. Another words on intake manifolds on chevys and fords. Front and rear rails. Over the years i have found beads of silicone in rocker shafts and oil pumps. Stay away from it if it is used where it is squeezed out thin. Normally sealers cause the gaskets to slip out and move. The chemical actually lubricates the two parts and makes a poor seal at best. Electronically controlled engines can NOT use any silicone at all. Unless it is an oem type that is sensor safe.Hope this helps
I spend money I don't have, To build  cars I don't need, To impress people I don't know

HAVE YOU DRIVEN A FORD LATELY!!

 

Silicon on Tranny Pan (84 Cougar, C4)

Reply #11
Permatex makes a good sensor safe sealant. When I do my tranny filter/fluid swaps, I always use a small trail of the black oil resistant sealant on the pan, set the gasket on the pan, flip the pan over (on a clean surface) with the gasket face down and use something that has a good bit of weight to it to set on top of the pan for about 5 or 10 minutes. Never had any problems and haven't had a leaking pan yet.
FOXLESS!!

1994 Lincoln Mark VIII


Silicon on Tranny Pan (84 Cougar, C4)

Reply #12
Was hoping this issue (silicone or Not to silicone) would get resolved in this thread.
Per original post OEM's have gone from None to uisng silicone in a number of places
including tranny pans.  In fact when Ford manufactured the 1984 Cougar, they used silicone
on the oil pan, differential cover, and timing cover.

Old school -- me and based on posts, a few others-- always said "no" silicone.
But is old school still correct?
Inquirying minds want to know -- with some evidence to back it up????

I do know, about two years ago I talked with the engineering staff at Permatex, and at that time
there was NO product that would completely remove the silicone.  My concern at that time was
if you sped off most, applied a new layer, and then the original older unsped
silicone broke lose, you have a leak.

Silicon on Tranny Pan (84 Cougar, C4)

Reply #13
I use a dry cloth and it removes the old silicone on flat surfaces, or a small brush. As far as using it on tranny panes. It's personal opinion. I've never had an issue using it, and never have I had a damaged tranny or engine from it. Using it correctly and in moderation, you'll be fine. My engine and trans are proof, Not a leak on them, and I didn't use it everywhere, but in a couple of places, yes, I used it. I don't have a trans. pan anymore. hen I did, I always used it without incident.
'88 Sport--T-5,MGW shifter,Trick Flow R intake,Ed Curtis cam,Trick Flow heads,Scorpion rockers,75mm Accufab t-body,3G,mini starter,Taurus fan,BBK long tube headers,O/R H-Pipe, Flowamaster Super 44's, deep and deeper Cobra R wheels, Mass Air and 24's,8.8 with 3.73's,140 mph speedo,Mach 1 chin spoiler,SN-95 springs,CHE control arms,aluminum drive shaft and a lot more..

Silicon on Tranny Pan (84 Cougar, C4)

Reply #14
Just wondering if someone can show me an OEM situation where silicone is used with a GASKET from the factory!!!!!!!!!!!!!!!!!

If you are hell bent on using sealers use IH GREY with no gasket. Silicone should not be used on gaskets. Toyota uses IH GRAY  on its V 6 motors not silicone. Silicone can be used like i said on intake front and rear rails.  I have seen silicone ruin many an engine and or tranny. Ask any diesel manufacturer if they recommend using silicone. Modern gaskets are made to not use any type of sealer. Sealers allow the gasket to move and not work correctly. Their is specific uses for silicones but its far and few between. If you feel it works for you GREAT. I personally rarely use it other than specific applications. Most of the new transmissions have special reusable gaskets on the pans. They even tell you so on the gasket. Never use silicone with a gasket. Just me could be wrong AGAIN

NOTE Ford used IH GRAY on their pans and differentials not SILICONE




Ratech reusable transmission pan gaskets. These reusable transmission pan gaskets are made of a rubber coated fiber material and are designed to be installed without gasket sealer. Give them a try--you'll be glad you did!
I spend money I don't have, To build  cars I don't need, To impress people I don't know

HAVE YOU DRIVEN A FORD LATELY!!