Transmission Pan Torque Sequence

[Merkava_4]

I've been trying to come up with a torque sequence for my 4T65E transmission pan gasket. I put the red numbers on myself. As you can see, it's an odd shape and there's 20 screws. I've been told you're suppose to use a criss-cross pattern, but that's a lot easier to do if you're working with rectangles or squares. If you guys can think of a better numerical torque sequence, PLEASE let me know.

 

[Colt45ws]

Its not really that critical. Just winging it when you put it together is more than good enough.

 

[pcoxe]

That, and torquing it down in stages rather than full torque in one pass.

 

[GreeCguy]

Originally Posted By: pcoxe
That, and torquing it down in stages rather than full torque in one pass.


Agree. Mine is a funny shape, (looks like the State of Florida). I just keep doing the criss-cross/opposite, (as close to opposite as I can get), snugging up all the bolts as I go and the final go round is torqued. No leaks, no problems.

 

[eljefino]

I use a cordless drill with "clicky torque" and adapter to fit the 10mm bolt heads. I zip 'em all down to 1 ft lb then go at it with a ratchet. As I use ramps I don't criss cross but rather just take several circular passes. The gasket has built in torque stops so it's really not that critical. I imagine me "chasing" a rubber bulge by going in circles which isn't that big of a deal IMO... it's not "trapping" it which could force it sideways.

My initial pattern is driven by reachability and the desire to have the built in funnel remain the lowest point in case of any still dripping ATF>

 

[doitmyself]

I agree that it's not such a problem if you torque it up in steps, maybe three or even four for us OCD.

Merk, what kind of gasket are you using? I love Felpro because they are thicker and are some kind of rubber that is harder/tougher (at least my AT gaskets).

Here's what I learned if you use a torque wrench on non metal gaskets (I imagine your looking at 9 to 14 ft. lbs. +/-). To me it seems that once you run it up to the the recommended torque, you should stop using the torque wrench. What seems (for me) to happen is that the gasket relaxes a bit and if you go around again (and again) with the torque wrench, it will continue tightening again to the recommended torque. The gasket then distorts.

If I use a torque wrench for this application, I use it kind of like a torque plus angle bolt. Torque it to the recommended number and let it be. If it begins to seep, tighten each bolt 1/8 to 1/4 turn until the leak stops.

I only bring this up because I know you are a tool geek and like to use what you have at hand.....correct? Those that only use their calibrated elbow torque meter on any and all fasteners can now add their snarky remarks

.

 

[Doog]

I would use your scheme and then just do 2 passes. Don't over think it. Plus us a thin coat of RTV on the metal to hold gasket and fill tiny voids.

 

[expat]

A classic case of 'going by the book' and getting obsessive about it, rather than understanding the issue, and what the goal is.

Torque in stages.

 

[Merkava_4]

Originally Posted By: doitmyself

Merk, what kind of gasket are you using?


It's that reusable rubber Felpro with the steel shim in the middle. I torqued it to 132 inch pounds and I'm thinking maybe 120 inch pounds would have been better. I know there's a torque pattern out there somewhere. They must've used a torque pattern at the factory when they built the car. I noticed Felpro has all kinds of torque pattern diagrams on their website, but I haven't found any for transmission pans yet. I may have to put a phone call in to Felpro tech support and see what they can do.

 

[Virtuoso]

Are you having leak problems? If not, I wouldn't sweat a thing!

 

[expat]

Originally Posted By: Merkava_4


I know there's a torque pattern out there somewhere. They must've used a torque pattern at the factory when they built the car.


I would bet, in production, all those fasteners were turned simultaneously.

 

[Merkava_4]

Originally Posted By: expat

I would bet, in production, all those fasteners were turned simultaneously.


That's probably true. I watched them do that with a Corvette cylinder head on YouTube.