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Topic: Something to remember when moving a bolt hole... (Read 5829 times) previous topic - next topic

Something to remember when moving a bolt hole...

So I decided that what I needed was a 4R70W trans pan, the capacity is a little more, and it's got that cute little sump that is perfect for a drain plug.  I found a new one just sitting under a bench, so I painted it, made a drain hole, welded a 12x1.75 nut inside the hole, and took it to the vehicle.  Once there I discovered that the pan rail was just 1 hole different compared to the AOD.  No big, bolt it on with all the bolts that DO fit, cut a new hole in the gasket through the misfit bolt hole, center-punch, 17/64 drill, 8x1.25 tap, and we're back in business.  New bolts in, lower the hoist, fill the trans, lift and check for leaks, and it's g out of the bellhousing. 
:punchballs:

I happen to know that the new hole went through into the bellhousing and I didn't think much of it.  Now I had a problem. Pulled the new bolt and like a windowlicker, I wrap it in thread tape and reinstall.  No change.
:shoothead:

I didn't plug the old hole and the gasket still has a hole there. I used my new drain plug, and almost right away the bellhousing quits running fluid.  Dropped the pan, checked, and sure enough, the old hole goes into the bell just like the new one.  I filled the old hole with grey RTV and left a blob hanging out of the hole to fill the hole in the gasket. Buttoned up, filled, checked and dry.
:burnout:
Point of advice:  When you move a bolt hole, get rid of the old one.

Something to remember when moving a bolt hole...

Reply #1
Another example of "It's just a bolt on".  At least the drain came in handy!

Something to remember when moving a bolt hole...

Reply #2
I have a drain plug on my stock AOD pan. It was really easy to do ;).
88 Thunderbird LX: 306, Edelbrock Performer heads, Comp 266HR cam, Edelbrock Performer RPM intake, bunch of other stuff.

Something to remember when moving a bolt hole...

Reply #3
Makes you wonder why they didn't add one from the factory.
2002 Honda Civic EX

1984 Ford Thunderbird Elan
5.0 CFI, T5, Dual Exhaust

Something to remember when moving a bolt hole...

Reply #4
Quote from: dragon574444;400281
Makes you wonder why they didn't add one from the factory.


Because they want the pan dropped for a tranny service. Not just an oil change!!
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!!

 

Something to remember when moving a bolt hole...

Reply #6
Quote from: TOM Renzo;400282
Because they want the pan dropped for a tranny service. Not just an oil change!!

True but I like the drain plug. It's a hell of a lot easier to drain the fluid and then drop the pan than it is to drop it when it is full of fluid. I've added a drain plug to the trans of every car I've owned to make fluid and filter replacement easier. I hate dropping the pan when it's full of fluid because ATF always misses the drain pan no matter how careful I am :hick:
88 Thunderbird LX: 306, Edelbrock Performer heads, Comp 266HR cam, Edelbrock Performer RPM intake, bunch of other stuff.

Something to remember when moving a bolt hole...

Reply #7
Exactly. ^^

ATF is known universally to cover more square inches of flooring, by volume, than any other liquid on earth. Except for maybe soda that spews out of a can after you drop it and it gets a hole.
'98 Explorer 5.0
'20 Malibu (I know, Chevy, but, 35MPG. Let's go brandon, eh)

Something to remember when moving a bolt hole...

Reply #8
A drain plug is good and i install them. But the manufacturer does not install them as they want the pan dropped cleaned and the filter serviced. BOTTOM LINE Could be wrong!!!
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!!

Something to remember when moving a bolt hole...

Reply #9
Good logic Tom, but you gotta admit that a drain plug makes it easier to get the fluid out, sans mess lol
'98 Explorer 5.0
'20 Malibu (I know, Chevy, but, 35MPG. Let's go brandon, eh)

Something to remember when moving a bolt hole...

Reply #10
I could use a lower profile plug though. what I've got now is your basic 12 x 1.75 o-ringed 15mm hex drain plug. Some ecotec engines I've seen have a very thin plug with a torx. I'm going to grab the next one I see.  The plug sits just a fuzz lower than the exhaust, and I don't like that.

Something to remember when moving a bolt hole...

Reply #11
Yeah, not good on a lowered car hitting a speedbump or something along those lines.
'98 Explorer 5.0
'20 Malibu (I know, Chevy, but, 35MPG. Let's go brandon, eh)

Something to remember when moving a bolt hole...

Reply #12
Quote from: TOM Renzo;400295
A drain plug is good and i install them. But the manufacturer does not install them as they want the pan dropped cleaned and the filter serviced. BOTTOM LINE Could be wrong!!!


You're probably right. I like to think some sadistic engineer thinks it's funny when the guy changing the ATF gets it all over the floor and his cloths. I put a drain plug in to spite him :hick:.
88 Thunderbird LX: 306, Edelbrock Performer heads, Comp 266HR cam, Edelbrock Performer RPM intake, bunch of other stuff.

Something to remember when moving a bolt hole...

Reply #13
I install drain plugs in all of my auto trannys right off the bat. Helps to keep things clean whenever I have to drop the pan to change the filter, which I do every 20K. Without one in place, it tends to be a pretty messy job.

Re: Something to remember when moving a bolt hole...

Reply #14
Pro-tip, making the transmission drain plug the lowest point of the car, then dropping said car on SN-95 springs is dumb.  Car is back to an AOD pan now.