[Irelands child]

I have a problem that is driving me nuts (well, nuttier). I've put 3 trans pan gaskets on the C4 that's in my car - all have leaked, always at the rear corners. The worst part about this is that the engine/trans have never run. I've only put oil into the engine (doesn't leak) the diff, (tiny leak at one stud, fixed) and 4-5 quarts in the trans - ALWAYS leaks. This one I glued in place with some spray seal. The TCI pan is straight including at the holes, the bolts are tight and are the flanged OEM Ford. There are no malformed holes or pulled threads in the trans body, there was no gasket material left on the trans or pan and no visible casing cracks.

I have another premium (Fel-Pro) pan gasket, and am about to drain the oil again (yes, I strain and reuse it, it's new). Fel-Pro cautions against using sealer, and by training, I have never used it here either - but this is getting real old and more drastic measures are needed. :smash:

Is there any reason that I shouldn't consider an oil resistant silicone type sealer? If any sealer were to break free, the filter would prevent clogging oil passages.

HELP

Thankfully the body is still off the car and access is good - which is about the only positive .

Thanks,
Dave

 

[302 Z28]

Dave
There is a reason for the leakage and use of sealer is not the answer. Either the pan is warped or the bolt holes have been distorted by over tightening. Take a straight edge and place it against the pans mating surface and look closely at the bolt holes to make sure they are completely flush, if not use a ball peen hammer to make them flush. I do not like the cork gaskets supplied in kits, I prefer the black composite gasket instead. The cork gasket is too easy to over tighten and cause a leak IMO.

Vince

 

[pasadenahotrod]

Have you checked the transmission housing gasket surface for flat and square? DOesn't the gasket tell you something when you drop the pan. Deformities in the pan impression in the gasket or something??!
The only times I have ever had any trans pan gasket leak is when I overtightened the bolts and pinched the gasket...drip drip drip. I try to use ATP brand gaskets when I replace the gaskets, use the same filter kit too.
Hope the sealant works for you.

 

[iyocum2]

Leaking C4

i had the same problem. It was not the pan gasket. The dip stick/fill tube was leaking and running back so it looked like the pan. A new O ring fxed the problem.

 

[Irelands child]

Dave
There is a reason for the leakage and use of sealer is not the answer. Either the pan is warped or the bolt holes have been distorted by over tightening. Take a straight edge and place it against the pans mating surface and look closely at the bolt holes to make sure they are completely flush, if not use a ball peen hammer to make them flush. I do not like the cork gaskets supplied in kits, I prefer the black composite gasket instead. The cork gasket is too easy to over tighten and cause a leak IMO.

Vince

Vince - The pan is straight according to my commercial size table saw top(that's my "granite" block for checking straightness), the bolt holes are flush, and the gasket has never been a cork piece of crap as I too think they are marginal - always a composite, 3 each ATP #FG126. The one on my bench now is a Fel-Pro TOS18634, also a composite and feels a bit thicker. I've built and used Ford C4 transmissions for well over 20 years and never had more than a damp spot but never a leak - and if this new gasket leaks, out the trans comes and in goes my freshly rebuilt spare. Then I'll do diagnostics on my workbench :sweat: .
Dave

 

[KULTULZ]

Either pulled threads (as mentioned) or possibly warped/damaged case opening (chiseling off of old sealer). If threads are pulled (get/use proper torque wrench), maybe smooth opening flange (counter sink threads) and use studs.

I wonder if anyone makes those neat little reinforcing rails like used on the engine oil pan?

 

[Irelands child]

Either pulled threads (as mentioned) or possibly warped/damaged case opening (chiseling off of old sealer). If threads are pulled (get/use proper torque wrench), maybe smooth opening flange (counter sink threads) and use studs.

I wonder if anyone makes those neat little reinforcing rails like used on the engine oil pan?

I do have a spare set of ARP studs - but what heluva job it is when you change a filter - you have to pull out all 11 to even remove the pan once it's been thru a few heat cycles.

The threads aren't (weren't?) pulled and the case wasn't gouged but I'll crawl under and re-countersink the holes (did it when I rebuilt it), install the studs and my new Fel-Pro gasket and see. Sounds like some fun for this afternoon.

I do like the reinforcing rails that are on the engine pan - the black rail looks like crap against the chrome, but works.
Dave

 

[red65mustang]

just use 2 gaskets......the pan "is" distorting under bolt tension which won't show up on your bench.....

 

[Irelands child]

New gasket, no distortion in the pan, chamfered the bolt holes and torqued the bolts to 15 lb.ft. Couldn't find the studs but the bolts are OEM flanged so have the same load spread. I was surprised that the bolts were quite loose as they were originally tightened to 12-15lb ft when I installed the last gasket. I went around the bolt circle at least 4 times, JIC it was screwed up the last time - of course by yours truly :embarrass .

I do appreciate all the responses.

Dave.

 

[65Stanger]

12-15 ft-lbs is over-tight. 100 inch-pounds, and you can even start at 90, go around once, and then go back around and go to 100 inch pounds. I bet your leak will stop. =D

 

[red65mustang]

65stanger,
read the torque chart in Irelands thumbnail....100inch lbs= 8ftlbs= way to loose

attached is another one for a C-4 to confirm his is correct, 12-16ftlbs

 

[tnsmith10]

I have a problem that is driving me nuts (well, nuttier). I've put 3 trans pan gaskets on the C4 that's in my car - all have leaked, always at the rear corners. The worst part about this is that the engine/trans have never run. I've only put oil into the engine (doesn't leak) the diff, (tiny leak at one stud, fixed) and 4-5 quarts in the trans - ALWAYS leaks. This one I glued in place with some spray seal. The TCI pan is straight including at the holes, the bolts are tight and are the flanged OEM Ford. There are no malformed holes or pulled threads in the trans body, there was no gasket material left on the trans or pan and no visible casing cracks.

I have another premium (Fel-Pro) pan gasket, and am about to drain the oil again (yes, I strain and reuse it, it's new). Fel-Pro cautions against using sealer, and by training, I have never used it here either - but this is getting real old and more drastic measures are needed. :smash:

Is there any reason that I shouldn't consider an oil resistant silicone type sealer? If any sealer were to break free, the filter would prevent clogging oil passages.

HELP

Thankfully the body is still off the car and access is good - which is about the only positive .

Thanks,
Dave

says here u have a tci pan.. it isnt by chance chrome is it??? if it is, thats why its leaking...
even though i normally dont support the use of silicone on transmission pans, this is 1 time it may be necassary to keep it from leaking... 1st wire wheel the surface of the pan, then put a very thin coating of silicone on the pan surface, then use a fiber gasket from a local trans shop... the ATF service kits their gaskets r maringal at best (IMO) and easily get pushed out the side... 12-13 ft lbs is all thats necassary for torque, otherwise u risk pushing the gasket out.. when done tightening, u should see just litle silcone "bubbles" coming out from the side... give it an hour of so b4 u put the fluid back in so everything can set... gl

 

[Irelands child]

says here u have a tci pan.. it isnt by chance chrome is it???

Yes -it's chrome - and yes, I'm aware of leaky chrome pieces like pans and valve covers and yes, my CRS set in and I FORGOT

If it continues to leak, I'll put either my grungy OEM pan on :nono: or fix this one :sweat:

Dave

 

[65Stanger]

All I'm sayin' is I torque every pan, make or model regardless, to 90-100 inch/lbs, and hardly ever does one leak on me. =D

 

[xntrik]

Torque settings be damned. Tighten gently and evenly in steps. Watch the edge of the gasket and when it starts to creep.... stop. You will see that nearer the bolt will creep more than between the bolts. stop.

Score the inside of the chrome pan gasket surface with a very coarse wire wheel.... lengthwise..

Scrub the pan rails and transmission with non residue brake cleaner thoroughly before installing. You could even hit it with electrical contact cleaner. Paper towel must stay white.

Use silicone installed PROPERLY. That means smoothly and let it set up for 20 minutes before installing. If done correctly it will not leak.

 

[Irelands child]

Waiting with bated (baited?) breath - no leak yet today.

Composition gaskets don't creep - only cork and I wont use them on trans pans. 12-16#ft torque (180 in lbs is what I used with my small torque wrench) which is correct for a Gr8 5/16 bolt.

If it still leaks, it looks like there are a lot of good suggestions on how to fix it :smash: .

Dave

 

[xntrik]

Waiting with bated (baited?) breath - no leak yet today.

Composition gaskets don't creep - only cork and I wont use them on trans pans. 12-16#ft torque (180 in lbs is what I used with my small torque wrench) which is correct for a Gr8 5/16 bolt.

If it still leaks, it looks like there are a lot of good suggestions on how to fix it :smash: .

Dave

Looking carefully you see it swell out as you tighten, that is what I was referring to.

 

[Irelands child]

I just said @#$% it and ordered a Trick Flow cast aluminum pan from Summit a few minutes ago ain: . The TCI pan started oozing at the left rear again. I removed it and checked it out. It's flat side to side, the bolt holes had started to distort a bit, but within normal limits and easily fixed with a ball pein hammer - but the chief culprit is that the Chinese dies didn't make a totally flat sealing surface - there is an area about 1.5 inches across the back that is rounded, not making a fully flat surface to seal and, guessing now, that when I pulled it tight, it warped a bit, just enough to leak. I miced the steel just for snickers - it's .035 vs. the OEM of .051. That's 16 ga for the OEM pan and 19 ga to the POS TCI pan - 3 gauge sizes thinner.

This has been an interesting lesson in frustration - the cheapie import stuff in many (most?) cases, is a waste of time and money. You buy what you think is a good brand name and it turns into more Chinese junk :smash: . I only can hope that the TFS pan is a good component now or another $98 is frittered away.

Guy - thanks for all the helpful suggestions. I guess I shoulda known that Chinese junk is .....junk.

Dave

 

[xntrik]

I'd try really hard to return it to TCI. Defective merchandise. Let us know how it turns out.

Save this address and post results. thanks :thumbup:

 

[Irelands child]

I'd try really hard to return it to TCI. Defective merchandise. Let us know how it turns out.

Save this address and post results. thanks :thumbup:

Most likely should but I've had it a long while (over 3 years) and probably can't find my receipt from Summit or Jegs