transmission pan bolts overtightened - what now?

juliecracker · **Posted:** Sun Sep 25, 2016 1:36 pm

did a big fluid and filter change yesterday. it all went really smoothly (thanks to many articles here and YouTube videos!). however, we were tired last night and set the torque wrench to the wrong setting when putting the transmission pan cover back on.

I'm not positive, but it's not unlikely at least some of the bolts are overtightened.

i haven't filled it yet. should I:

1. remove all the bolts, replace the gasket and do it again the right way

2. leave it and hope for the best

3. back them out and retighten properly

4. something else

thanks for any and all suggestions!
julie

papaindigo · **Posted:** Sun Sep 25, 2016 2:09 pm

First off I'd say in the future don't bother with a torque wrench for these sort of bolts. Run them down snug and give them a bit more of a twist by hand would be fine (e.g. good and tight is good enough). That said if you did not break any they are not "too" over tightened hence I'd be inclined to add ATF+4 and leave the bolts alone. Gasket shouldn't leak unless somehow you managed to warp the tranny pan which I doubt. If you try to remove and redo you run risk of twisting a bolt head of "now" as opposed to ca. 50,000 miles from now when you do a fluid change again.

Wonder what others think.

flash7210 · **Posted:** Sun Sep 25, 2016 3:06 pm

I think it depends on the type of gasket material.

If its old style cork gasket, overtightening will casue the gasket to split and it will definitly leak.

If its new style black rubbery gasket, they are more durable and usually wont leak.

My technique for trans pan gaskets is the same regardless of material:
1. Spread a small bead of black rtv on the pan
2. Lay the gasket on the pan so it sticks to the rtv and all the holes line up
3. Lightly dampen the trans side (up side) of the gasket with atf
4. Spin the bolts on with only a 1/4 drive socket and extension. Just hand tight. Then use a ratchet to snug them up a bit more.

If done right, it wont leak and next time you remove the pan the gasket will come off clean and will probably be reusable.

juliecracker · **Posted:** Sun Sep 25, 2016 4:12 pm

thanks so much for the quick responses! it has only black rtv. no gasket.

we did break one bolt. so we backed off but still probably overtightened a bit. (it's the first time we've used the torque wrench - I thought I was being more thorough by finally pulling it out of the tool cabinet... sigh.)

so is leaking the only concern? Or bending the pan (which would also result in leaking)? I was worried that the transmission case might crack if a bolt was cranked down too tight, especially once it's full of fluid and heats up.

(this is my first time doing a transmission service....)

geordi · **Posted:** Sun Sep 25, 2016 5:17 pm

Leaking is the only concern, the pan is stamped steel and the case is cast aluminum - the threads in the case will suffer if you strip them, but you can just bend the pan around if you needed to.

Chances are you are just fine, especially with RTV. I'd just fill it and run it.

Don't forget: You cannot trust the "full" mark on the dipstick, the trans stick is too long and will lead to a LOW reading! Plan on at least 7-8 quarts of fluid to get it full, and possibly 9. How it feels is your indication of whether it is correct or not. Smooth shifting and engagement is good, high revving and hard shifting is not.

transmission pan bolts overtightened - what now?

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