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Can I switch to deep tranny pan from shallow?

3K views 10 replies 5 participants last post by  the_bruce 
#1 ·
97 Safari RWD - 100K miles

I am doing a transmission fluid change (not the flush option, did not want to dig into the radiator connections). I installed a drain plug in the pan, but upon reassembly it will not let the pan seat correctly. Stupid me put the drain in a bad place and the inside bolt is hitting something.

So, I can either try again with a new shallow pan trying to put the drain in an acceptable place and hope it works, or I was thinking of getting a deep pan and filter to allow more room. I think both the shallow and deep pans have 16 bolts, and gaskets look the same so as long as I got the correct filter I think it would work. Anyone done this?

Also, one of the short bolts sheared off while taking off the pan :banghead: I was going to put together once I get the drain location figured out and see if it leaked once all the bolts are torqued correctly. Anyone ever remove a broken tranny pan bolt?

Everything seems to take me three times as long as I think it should and there is always some SNAFU that pops up. :whack:

Thank you,
Bruce
 
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#3 ·
Pans bolt up the same, just change to the proper filter.
Do you have a picture of your pan and the new drain that you installed, so others can see where not to put the drain?

As far as the bolt, drill it, start with a small pilot and make sure it's centered and straight so you don't damage the threads. Otherwise if there is enough to weld a nut to the remaining bolt, you can use that to remove it.
 
#5 ·
Deep pan works fine, just get a deep filter.

I took mine off a tahoe trans I think.

It's too bad you drilled the wrong spot on the original though - did you not put it in the circular depression?
 
#6 ·
AstroWill said:
Pans bolt up the same, just change to the proper filter.
Do you have a picture of your pan and the new drain that you installed, so others can see where not to put the drain?

As far as the bolt, drill it, start with a small pilot and make sure it's centered and straight so you don't damage the threads. Otherwise if there is enough to weld a nut to the remaining bolt, you can use that to remove it.
Thank you, that sounds like a pan plan. And the bolt sheared off just a tad above the bottom of the tranny pan mating surface. I have seen a video where a guy inserted a small section of copper line to shield the threads and he used a mig welder to tack on little bits until it was out of the hole, then welded an old screw driver to the weld. Could do a nut too. Came out easy for him, but I am used to having more trouble with this type of thing.

I was going to try a screw extractor but drilling in the tranny makes me extremely nervous. Would take half a second to go very bad if I got into the threads.

Bruce
 
#7 ·
#8 ·
SportsBoy said:
Deep pan works fine, just get a deep filter.

I took mine off a tahoe trans I think.

It's too bad you drilled the wrong spot on the original though - did you not put it in the circular depression?
The stock pan was one of the flat ones, no depression except a few lines where the magnet goes. I got ahead of myself installing the drain plug on a rainy day before I could pull the old pan off and get a good look for placement. Thought I'd have enough room on the rear corner of the pan, but au contraire.

I will take pictures of the badly placed drain plug so all can learn from my blunder.

Bruce
 
#9 ·
the_bruce said:
SportsBoy said:
Deep pan works fine, just get a deep filter.

I took mine off a tahoe trans I think.

It's too bad you drilled the wrong spot on the original though - did you not put it in the circular depression?
The stock pan was one of the flat ones, no depression except a few lines where the magnet goes. I got ahead of myself installing the drain plug on a rainy day before I could pull the old pan off and get a good look for placement. Thought I'd have enough room on the rear corner of the pan, but au contraire.

I will take pictures of the badly placed drain plug so all can learn from my blunder.

Bruce
Ah, gotcha - I couldn't remember what the original pan looked like
 
#10 ·
:ty: Thanks for the tips! With my latest Amazon delivery I am now loaded for bear... I have got:

-deep pan filter
-Dorman deep pan w/drain pre-installed (quality seems good, drain plug assembly looks reasonably solid and has an aluminum crush washer included)
-new OEM pan bolts
-M8 x 1.25 thread tap in case the two bolt holes with galled threads give me any sass :whack:
-RIDGED screw extractor set for the broken bolt
-and, just in case the bolt extraction or thread chasing goes to hell in a handbasket, a helicoil kit.

Not messing around this time. This van WILL be on the road this weekend come hell or high water. :rockon:

Just in case the helicoil is necessary, does anyone have any tips for installing in aluminum? Some sites say use thread cutting oil, some say use special aluminum oil, some say don't use any at all in soft metals which concerns me a little.

-Bruce
 
#11 ·
Follow up: New pan worked great. Used a tap on the galled threads on either side of the broken bolt, was VERY VERY VERY careful about threading it properly so as to not cross thread. Minimal material removed in the tap channels so I don't think I boogered them up. Got new bolts to replace the ones that looked like they'd gall the threads on re-install. Said a few hail Marys (haven't been to mass for 25 years so that might have been a jinx) and ever so gently and evenly torqued the bolts up, leaving the broken one in place. With the new gasket and pan, it seems to be leak free. Been driving it for a month and a half and religiously checking for drips and leaks, so far nada. Super glad to have the drain plug, I don't think I will ever try to remove that pan again since it gave so much trouble.

Tranny is shifting as good as ever, this was just preventative since it had never been done in the 100K life of this van. I plan on doing another drain and fill soon. After 5 or 6 iterations it should be all new fluid.

Word to the wise: clean the upper tranny pan bolt holes of the before removing the pan bolts. I thought I did, but there was evidently still some grit which was pulled into the holes when I unscrewed them. Power wash, use brake fluid, I don't know what but make damn sure they are clean. Especially behind the heat shield next to the exhaust since crap seems to collect there.

This weekend: new AC compressor, dryer and orifice tube, then I plan on evacuating system with newly purchased pump and gauge set. Had a shop leak test and they said only place they saw a leak was compressor shaft. If it holds vac for a few days I will recharge. Wish me luck, it's been a hot one so far and this old van has not had air for 15 years :banana:
 
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