C3 1969 THM400 Oil Pan

[Craig C.]

The transmission oil pan on my '69 427/THM400 does not come close to looking like the original. Does GM still carry an original style THM400 pan? If so, does anyone know the part number and approx price?

Any help on where to look for an original looking trans oil pan for this car is appreciated.

Thanks,

Craig #32671

[Joe L.]

Re: C3 1969 THM400 Oil Pan

Craig------

Your problem stems from the fact that the SERVICE oil pan for the 68-77 THM-400 has changed a few times since your car was built. The original transmission pan for your application was GM #8625766, but it was discontinued from SERVICE in August, 1985. The current replacement is GM #8679995. As you've found, the configuration of this pan is different.

I don't know if there are many NOS examples of the original pan around since it was discontinued so long ago. Your best bet might be to go to a transmission rebuild shop and see if they have some good, used original-style pans around. You might even offer to swap it for your NEW replacement pan. For the tranmission rebuilder, the NEW replacement pan might be more valuable than the used original. Transmission rebuild shops are usually more interested in functionality and desirability for MOST customers than original configuration. MOST customers prefer NEW parts to USED parts, original or not.

The current pan, GM #8679995, GM lists for $72.29.

[Jim T.]

Re: C3 1969 THM400 Oil Pan

Craig I replaced my 70's turbo 400 tranmission pan many years ago with the GM replacement #8655021. This was in May 1990, the cost list was $27.00 and the net price was $20.25. This replacement pan is a heavier guage metal than the original in thickness. There is a very noticeable weight difference. I replaced my original pan because I wanted a stronger transmission pan to give a better gasket seal. I had changed my fluid and filter on my 70 a few times and could never maintain a good seal without some fluid getting past the gasket. I always used a torque wrench to tighten the pan bolts also. With the new transmission pan I have not experienced any leaks around the pan gasket.