Silverado transmission pan removal

[ssspencerjr]

Didn't think it would be this difficult. I'm trying to drop the pan on my 04 Silverado 4x4 and I have 2 issues.

1. The drain plug is rounded off, I guess this is common being old, crap metal with shallow head and overtightened from the factory.

2. There isn't enough clearance to drop the pan without dropping the exhaust down by removing 3 bolts from each exhaust side.

Does anybody have any tips for removing the rounded off drain plug as well as breaking loose the factory exhaust nuts on the studs?

 

[Snagglefoot]

For the exhaust nuts, plenty of heat, preferably Oxy Acetylene. If you don’t have a set-up you could go to a muffler shop and ask them to replace the nuts with new ones. OA burns at over 6000 F making it much hotter than Propane or Mapp which are both in the 3600 -3750 F range. If they are not that rusted you could try a Mapp torch and then give the nuts plenty of rust penetrant.

For the rounded drain plug, perhaps have the muffler shop weld a piece of metal to look like a lever on it.

 

[Lubener]

Vise grips, channel lock pliers for alteast the drain plug. If the bolt head isn't too large, there are special sockets made to remove rounded bolt heads by biting in while trying to loosen it.

 

[ssspencerjr]

Vise grips, channel lock pliers for alteast the drain plug. If the bolt head isn't too large, there are special sockets made to remove rounded bolt heads by biting in while trying to loosen it.

Thanks for the info. I already bought a set with the reverse spiral flutes. The metal is so soft it just kept rounding it off, I even pounded a smaller size onto the head, same thing.

 

[vwmaniaman]

Next time buy a Ram.

 

[ssspencerjr]

For the exhaust nuts, plenty of heat, preferably Oxy Acetylene. If you don’t have a set-up you could go to a muffler shop and ask them to replace the nuts with new ones. OA burns at over 6000 F making it much hotter than Propane or Mapp which are both in the 3600 -3750 F range. If they are not that rusted you could try a Mapp torch and then give the nuts plenty of rust penetrant.

For the rounded drain plug, perhaps have the muffler shop apiece of metal to look like a lever on it.

I bought a Bernzomatic kit just to try this. The studs/nuts are somewhat rusted being exhaust and all, but luckily I live in the south and the truck was never in the north, so it's not anywhere near what it could be.

I had heard of people welding a bigger nut over top of the plug and being able to remove it that way, but I've never welded nor do I have the equipment.

Maybe I can try the vise grips with heat after I get the pan off?

 

[ssspencerjr]

Next time buy a Ram.

lol no thanks.

 

[PontiacHO]

If it’s just for fluid change use a top side oil change pump and draw the fluid up/out of the dipstick tube. The same amount of trans fluid is drawn out vs drained. If there are problems with the trans dropping the pan won’t solve them.

 

[ssspencerjr]

If it’s just for fluid change use a top side oil change pump and draw the fluid up/out of the dipstick tube. The same amount of trans fluid is drawn out vs drained. If there are problems with the trans dropping the pan won’t solve them.

Trans is good. I just bought the truck with low miles and the fluid had never been changed. I really need to change the filter, which is the reason for me wanting to drop the pan.

 

[Chris142]

Is it the OE exhaust? I serviced the Trans on our 04 tahoe and did not have to mess with the exhaust. I do remember having to remove the bracket for the shift cable but that was only 1 or 2 bolts

 

[Chris142]

Trans is good. I just bought the truck with low miles and the fluid had never been changed. I really need to change the filter, which is the reason for me wanting to drop the pan.

Really no reason to change the filter. If it is plugged the trans is doomed anyway.

 

[ssspencerjr]

Is it the OE exhaust? I serviced the Trans on our 04 tahoe and did not have to mess with the exhaust. I do remember having to remove the bracket for the shift cable but that was only 1 or 2 bolts

It is OE. I think there may be some torx bits on top, but I can't get my hand up there or even see above the trans.

 

[tyman]

I know on the NNBS (07-13), there's enough flex in the exhaust that most guys will either use a crow bar to push it down or get a jack/2x4's and ratchet it down. I had an upgraded catback on mine when I dropped the pan last year and there wasn't enough flex in it so we had to drop the exhaust. Broke 2 bolts on each one, thankfully I had already gone to Autozone and bought a new exhaust bolt kit so we ended up taking all 3 from each off and put all new ones on. You only need to flex the exhaust about an inch or so out of the way to drop the pan...but what a stupid design on GM's behalf. The next time it comes up, I'm getting one of the aftermarket pans with a drain plug....absolutely stupid.

 

[Snagglefoot]

Here is an A-1 Auto video on the topic. Of course in their version the exhaust is not rusted tight.

 

[Rat407]

I had to get a bolt out kit. They are not expensive and I got my at Sears a long time ago. Worked like a champ.

Also on the GM-Trucks forum, it is an issue with the exhaust. Some pull down on the exhaust and loosen the bolt to the transmission crossover mount and push up on the transmission. It didn't work for me on my 2016 suburban so I had to loosen the exhaust. Some are able to get the filter out without removing the pan.

 

[PontiacHO]

Really no reason to change the filter. If it is plugged the trans is doomed anyway.

So true. The potential for more problems can be created by disassembly to gain access for pan removal than is necessary. Draw the fluid from the top at annual intervals and the trans will last the life of the truck. Unless of course you just want the challenge of dropping exhaust etc. etc. etc...

 

[AutoMechanic]

Get a bolt out kit or a spline socket and get on there and take out the rounded bolts. You maybe able to get a wrench on top the exhaust to get those bolts out.

 

[mattd]

Turbo sockets are a great investment.

 

[4WD]

For the exhaust nuts, plenty of heat, preferably Oxy Acetylene. If you don’t have a set-up you could go to a muffler shop and ask them to replace the nuts with new ones. OA burns at over 6000 F making it much hotter than Propane or Mapp which are both in the 3600 -3750 F range. If they are not that rusted you could try a Mapp torch and then give the nuts plenty of rust penetrant.

For the rounded drain plug, perhaps have the muffler shop weld a piece of metal to look like a lever on it.

When dealing with the Ford PTU … had the muffler guy cut a section of pipe out and modified it just enough to give me room. He’s a one man show where cash is king and he did it good - but cheap … even left me enough room to wrap header tape on the pipe

 

[ssspencerjr]

I know on the NNBS (07-13), there's enough flex in the exhaust that most guys will either use a crow bar to push it down or get a jack/2x4's and ratchet it down. I had an upgraded catback on mine when I dropped the pan last year and there wasn't enough flex in it so we had to drop the exhaust. Broke 2 bolts on each one, thankfully I had already gone to Autozone and bought a new exhaust bolt kit so we ended up taking all 3 from each off and put all new ones on. You only need to flex the exhaust about an inch or so out of the way to drop the pan...but what a stupid design on GM's behalf. The next time it comes up, I'm getting one of the aftermarket pans with a drain plug....absolutely stupid.

It is a dumb design for sure. Doesn't help that I thought I could do a drain and fill using the drain plug provided, that plan didn't work out so well.