before i put the new engine and convetor back in, thought i'd change my trans oil and filter.
so, where is the preferred position to put a drain plug on the pan whilst apart?
on the side, front, back?
will advoid the bottom, dont want to wipe it off on a sped bump..

what a silly idea not to put one on when made

 

I put mine at the very rear of the pan, low on the rear face of the pan. I did not put it on the bottom surface, as I thought it was too noticible there. You only need to drain enough fluid that you don't spill it all over yourself; so that [rear-facing] drain plug is still low enough to get that job done.

Make sure that ALL of the sealing face on that plug & washer are on a flat surface. Don't let it creep into the radius where the rear face and bottom face meet, or it will leak. Also make sure that the parts of that drain plug on the inside of the pan will not interfere with any hardware when you install the pan.

Putting it on the bottom face toward the rear would allow more oil to drain out; but I think the 'rear face' mounting of the drain plug is better.

 

You're naive. GM intended for you to take your car in to your GM dealer for tranny fluid changes. That means there is nothing "$illy" about the absence of the drain plug.

 

thanks

 

When you change engine oil do you change the filter ?

The purpose of having to drop the pan is to get to the filter , it also allows you to determine the transmissions health at each service.

Performing the service the right way is the best way

 

GM didn't put a drain plug on the transmission pan because THEIR warranty period would have been over well before the tranny needed service. So...KA-CHING!!...saved more money by not including a drain plug.

But, that is just ONE example of why the Japanese vehicles ate GM's 'lunch' {starting in the late 1970's}. The J-cars paid attention to the whole life-cycle of the vehicle. GM only cared about the time THEY were 'on the hook'.

 

I have a B/M deep pan, the drain is located on the drivers side but if i was going to do my own i would suggest the back of the pan.

 

this time i'll put up with the mess when the pan is unbolted

i just dont want to make a mess when i remove the pan next time...

 

http://www.northerntool.com/shop/too...5124_200475124

A drain plug would be easier, I suppose, but it is an option. My brother has something similar, we've used when unintentionally over-filling tranny or engine oil.

Scott

 

How are you going to reinforce the area around the plug?

 

I braze these in.. Or use a weld in plug.

The ones with the plastic washer are "fiddly" imo..

 

Actually that can not be further from the truth.

The reason is you must pull the pan on a transmission service. A plug just lets a slick shop cheat ya on a fluid change. ( Valvoline lubes offers a flush what a waste of money )

Does anyone know why trans fluid can be slated for 100k or 50k before service ? Unlike engine oil the trans fluid has no out side contaminates to get into it. Your engine burns it own death each time it fires and contaminates the oil with blow by. A transmissions only contaminates come from itself.

Pulling the transmission pan allows a tech to base overall condition of the transmission by inspecting the pan. And a drain plug just encourages people and shops to perform a half A@# service .

Not against a drain plug for qualified people like a lot of us here because it does help in the process, but it is not a replacement for taking the entire pan off.

 

Bull-hockey..... None of that was even a consideration when GM tranny pans were designed. Automatic trannies are open to the outside air, as they MUST breathe. That's why there is a vent on every one that was ever made. And, the transmission makes its own contamination....all the clutch plate facing materials that wear off during the normal course of operation. There are also bronze bushings that wear with use.

I'm not sure where you came up with your "theories", but I find them very 'questionable'.

 

Your theory is off the hook . lazy ,unconcerned GM.

Tranny service requires pan removal fact , not a guess and that is for the inspection of the unit AND filter replacement.

Fact that air tube is there to prevent foaming of the fluid .

Fact as i stated the contaminants we find in the pan COME FROM THE TRANSMISSION this allows us to judge overall condition of the unit.

To have a drain plug is fine BUT it is not a substitute for pan removal. Matter of fact If I had a 100 for every th400 user who changed fluid and not filter and ended up with no gear engagement I could buy several TH400 units..

 

I worked for GM for 40 years. I understand what drives items that make it to production and those that don't. Check out the latest 'fiasco' by GM...stifling a possible recall because the 'repair' would have cost them $1 per car. And, the end result was the loss of at least 12 lives. Don't lecture me about how GM does things for the 'public good'. They do the things that make them the most money.....PERIOD.

 

"GM didn't put a drain plug on the transmission pan because THEIR warranty period would have been over well before the tranny needed service. So...KA-CHING!!...saved more money by not including a drain plug"

All a drain plug does is allow an inexperienced person to drain the fluid it is not a Ka Ching moment .. Transmission service should be done by experienced people.. People call constantly " Dave my mechanic told me to get my bands adjusted , joe at so and so auto said change the fluid cause it seams to not have 3rd gear.I have burnt fluid I need it changed and the list is endless.

If you cant drop a pan and not get oil everywhere you are inexperienced . . If you do change it and get a gasket leak your inexperienced. And if you think a fluid change or band adjustment will fix something your clueless ..

If you can pay attention to detail and know what your seeing when a pan is off and remember to remove the O ring from valve body where the filter neck installs then add a drain plug if your forced to do it on your back. BUT I never said DONT add it I am saying trans service with oil only is silly at best.

 

I just had my transmission fluid changed today in my DD Honda Civic Si. Drain plug, no filter to change - as per Honda manual; just 3 quarts of Honda specific fluid and clean the drain plug magnet. The internal filter needs the entire tranny removed to get to it. Manual calls for fluid changes every 50,000 miles and no mention, even at the dealership, of filter replacement. Go figure.

 

I have a trans pan with a drain plug. Sure is a lot less messy when pulling the engine and trans.

Zorro

 

There is little to risk by having "inexperienced people" change the filter and oil in an automatic tranny. You pull the pan; you pull the filter. You clean the junk out of the pan and inspect for any metallic content. 99% of the time, you then install the new filter, put on a new gasket, and button-it up.

But IT'S REALLY, REALLY MESSY if you don't have a drain plug.