XtremeVette

Mine is a 1990 in particular, but was curious if any c4 had a drain plug for the torque converter.

reeltime299

My 86 does not, Ive never heard of a converter having a drain plug.

ToddAT

The GM service manual for my 86 gives a procedure for drilling a certain size hole in a certain place in the housing to drain the fluid. Then, to seal it up, you use a screw and rubber washer. Swear to God that's what it says. I don't know about you, but it sounds kind of hokey to me.

Marcho Polo

Drain plugs are not standard on any torque converter. I have seen in the manual where it describes how to tap for one, but I've been told it's not recommended to do this. If you want to get the fluid out, go to an oil change place that can hook up the lines to the coolant line at the radiator and then they flush the system while the car is running.

ROADAPPLE

If you want to drain the converter while it's in the car remove the transmittion oil cooler line at the radiator, start the car and the pump will pump out all the oil in the converter. It only takes a few moments and no damage is done. This procedure is done usually when someone wants to change to synthetic oil.

DWS

mash557

I must disagree with Craig about there not being drain plugs on any converter. GM maybe, but a Ford I had several years back had one. I don't know if they still do, but in 1976 they did.

Ray Zavorka

Drilling a hole for a drain in the outer shell of a torque converter and then running a tap into it is not new at all, nor is it a risky proceedure for a competent and carefull mechanic. It is the correct proceedure!

I can remember doing this proceedure in shops as far back as I can remember. The reason that the GM manual suggests using a screw with a rubber washer is because of space limitations. Years ago we used to use a tapered 1/8" NPT pipe plug with a hex head. Today in most applications there is insufficient space for this proceedure (hits starterdrive etc.) hence the reason for GM's screw reccomendation.

I take very strong exception to any suggestions relative to using the transmission pump and coolant lines to expell fluid. BALONY! You will be takeing the risk of starving a critical component of fluid, creating a higher than normal fluid flow which will tend to circulate debris that would normally stay in the pan. I know that we will have folks who advocate this proceedure claiming that they have done it. I believe in the old adage "Better safe than sorry"

Ray

Mr Mojo

My 68 Dodge has a drain plug for the torque converter.

89 Bob L

I agree with Ray. Some older cars did have drain plugs on the converters. Converters can be drilled and tapped. It is extremely risky to remove fluid from transmission lines while the car is running.

NoWorries

Several Furds have 'em.

In order to do it right, the TC needs to be on a balancer and you have to offset the weight of the plug on the other side.

5 grams @ 5,500 rpm=

Ray Zavorka

The weight of about a #10x1/2" machine screw will be insignificant at best. If you are really a hot dog bad *** , grind off some material on the opposite side (180)degrees on the flex plate or something - this would be total overkill!

Ray

NoWorries

Ray, there is no way that 5 grams is insignificant, especialy a those speeds, and at the radius of the weight.

We balance tailrotors on our helicopters by adding washers, often we'll only add one to quell a violent vibration. That weight is only at a radius of about two inches.

On a helicopter, 5 grams off will cause the tail boom to see extreme fatigue in short order.

The results can only be similar in TC applications. You are going to throw the crank shaft out of balance, as well as fatiguing the crap out of the input shaft on your transmission.

NoWorries

I forgot to mention, the tailrotor on one of our Bell 206L's is only spinning 2515 rpms, our Sikorskies are only around 1500 rpms.

Ray Zavorka

First of all, the screw does not weigh 5 grams...

And even if id did, the stock engine is not balanced that closely. Go and have a production Chevrolet engine balanced and you will find variances that exceed 5 grams any way.

Like I said, if you are worried about it, grind of material to compensate for it - What do you think that balancers do with connecting rods and wrist pins - the grind them down.

And by the way, the military helicopters that I flew viberated so damn badly, I don't know how it could have been made worse with only 5 grams!

Ray