C-4 Transmission Drain Plug - Ford Muscle Forums : Ford Muscle Cars Tech Forum
 
LinkBack Thread Tools
post #1 of 9 (permalink) Old 04-24-2009, 09:22 PM Thread Starter
Registered User
 
Join Date: Jun 2004
Posts: 423
C-4 Transmission Drain Plug

Here is a small project that almost anyone can do and will greatly ease the maintenance of any automatic transmission. It is the installation of a drain plug on the transmission pan. All it took was for me to change the oil and filter once to realize that the addition of a drain plug would make the job far easier and cleaner.

Here is the pan without any drain at all:


There are bolt on drain kits kits available that only require a hole to be drilled, but since I had access to a welder, I made my own kit. I used a 1/2"-20 nut, and a plug off an old oil pan, The gasket is available at any parts store:


I decided to add the plug at the left front side of the pan so that the plug would not be in the way if it were on the bottom. A 9/16" hole was drilled first:


The paint around the hole was cleaned off with a wire wheel on a bench grinder in preparation for welding:


The nut was then clamped into position over the hole:


I used a MIG welder to weld the nut to the pan. The plug was installed, and the pan was filled with water to check for any leaks, fortunately there were none:


A little paint, and it is done. This was an easy to do project that cost nothing, and will greatly add to the ease of maintenance on the vehicle:
Attached Thumbnails
Click image for larger version

Name:	cover.jpg
Views:	14020
Size:	9.4 KB
ID:	7903  

'65 Mustang A code Fastback-in the works.

Last edited by Mikelonis; 04-25-2009 at 04:48 PM.
Cupcake65 is offline  
Sponsored Links
Advertisement
 
post #2 of 9 (permalink) Old 04-26-2009, 10:24 AM
Tech Contributor Gold
 
Join Date: May 2006
Posts: 114
Re: C-4 Transmission Drain Plug

Nice! I will be doing that one when I get around to a transmission project on my car.

Richard
1966 Mustang Coupe
\'95 roller 302, auto
warmed up just a little
check out my site: http://budgetrestomod.weebly.com/index.html
rmousir is offline  
post #3 of 9 (permalink) Old 04-26-2009, 08:58 PM
Subscriber
 
Join Date: Mar 2007
Location: Jacksonville, FL
Posts: 173
Re: C-4 Transmission Drain Plug

Thanks for that. You saved me $100 on a new pan!

'91 Mustang Coupe(Drag Race Only), Scat 331 rotating assy, Mighty Demon 650,Vic. Jr heads, Vic. Jr Intake, Comp cam 579 lift., 4.10 gears
Best 1/4 mile E.T so far: "[email protected]"
jagfandaddy is offline  
 
post #4 of 9 (permalink) Old 04-28-2009, 08:12 AM
Tech Contributor
 
Join Date: Nov 2004
Location: Levittown, PA
Posts: 980
Re: C-4 Transmission Drain Plug

cool, Ive received a few transmission with home made drains just never got around to doing it. Ive seen them on the bottom as well.

Brian


65 mustang, always progress involving work

BCP Custom -> Welding, Fabricating, Customizing, and Detailing

BCP Custom on Facebook
trashline is offline  
post #5 of 9 (permalink) Old 04-29-2009, 11:21 AM
Subscriber
 
Join Date: Dec 2002
Posts: 186
Re: C-4 Transmission Drain Plug

Don't put one on the bottom. If you car is lowered and you go over high man hole cover or if there is something in the road, you could shear it right off. I've seen it before.
dablack is offline  
post #6 of 9 (permalink) Old 07-11-2009, 03:55 AM
Registered User
 
Join Date: May 2009
Posts: 29
Re: C-4 Transmission Drain Plug

Quote:
Originally Posted by dablack View Post
Don't put one on the bottom. If you car is lowered and you go over high man hole cover or if there is something in the road, you could shear it right off. I've seen it before.
hi
i got my 1970 mach 1, 3spd..... could not figure out why there was no drain hole.
great answer--- i thought it was a stupid idea by ford but i guss tha why i don't build cars....
thanks,molly
molly is offline  
post #7 of 9 (permalink) Old 07-11-2009, 04:05 AM
Registered User
 
Join Date: May 2009
Posts: 29
Re: C-4 Transmission Drain Plug

Quote:
Originally Posted by Cupcake65 View Post
Here is a small project that almost anyone can do and will greatly ease the maintenance of any automatic transmission. It is the installation of a drain plug on the transmission pan. All it took was for me to change the oil and filter once to realize that the addition of a drain plug would make the job far easier and cleaner.

Here is the pan without any drain at all:


There are bolt on drain kits kits available that only require a hole to be drilled, but since I had access to a welder, I made my own kit. I used a 1/2"-20 nut, and a plug off an old oil pan, The gasket is available at any parts store:


I decided to add the plug at the left front side of the pan so that the plug would not be in the way if it were on the bottom. A 9/16" hole was drilled first:


The paint around the hole was cleaned off with a wire wheel on a bench grinder in preparation for welding:


The nut was then clamped into position over the hole:


I used a MIG welder to weld the nut to the pan. The plug was installed, and the pan was filled with water to check for any leaks, fortunately there were none:


A little paint, and it is done. This was an easy to do project that cost nothing, and will greatly add to the ease of maintenance on the vehicle:
HI

GREAT PIECE OF WORK...... I'VE GOT A 3SPD ON THE FLOOR IN MY MACH 1. DO YOU THINK THIS COULD WORK ON MY 3SPD MANUAL TRANS, REPEAT MANUAL NPT AUTO????
REALLY NEED HELP! EMAIL ME AT
[email protected]. my posts arn't
gettin thru for some reason.

molly
molly is offline  
post #8 of 9 (permalink) Old 07-11-2009, 04:16 AM
Registered User
 
Join Date: May 2009
Posts: 29
Re: C-4 Transmission Drain Plug

HI

NOT SURE MY POSTS ARE GETTING THRU. IF YOU GOT THIS ALREADY IGNORE IT.
DO YOU THINK THIS MIGHT WORK ONMY MACH1 1970 3SPD MANUAL TRANS?

THANKS,MOLLY
EMAIL [email protected]
molly is offline  
post #9 of 9 (permalink) Old 07-11-2009, 04:49 AM
Tech Contributor Gold
 
Join Date: Dec 2004
Location: Amish Wonderland Of Central PA
Posts: 4,909
Garage
Re: C-4 Transmission Drain Plug

Molly,

Unfortunately your 3 speed manual transmission does not have a removable pan like the automatic shown above.

Your transmission case is cast iron and could possible be tapped without adding additional support if it is cast thick enough. The problem with tapping it in this way is that the case may not be thick enough. Also metal shavings could be introduced to the inside during the process. This could bad so the transmission would need to be first dissembled to do the work.

If the case is not thick enough, then some type of additional support would be necessary. Unfortunately, it is not easy to weld to cast iron. It tends to crack when not cooled properly so it would require the professional services. Again, the transmission would need to be disassembled to do this.

For these reasons I feel that is probably not practical in your case to add a drain plug to that transmission.

By the way, have you looked at the underside of your transmission to see if it already has a drain plug? I haven't had a 3 speed in my hands for years but I do know that many (but not all) of the 4 speed transmissions available in the Mustang have a drain plug from the factory.

Dennis

65' Stang Street/Strip. Dart 434W NA, Victor heads, G101A 4 Spd, 4:56 rear gear, on 93 octane pushing 3550lbs. [email protected]

Last edited by dennis111; 07-11-2009 at 04:54 AM.
dennis111 is offline  
Sponsored Links
Advertisement
 
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the Ford Muscle Forums : Ford Muscle Cars Tech Forum forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in











Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page



Similar Threads
Thread Thread Starter Forum Replies Last Post
1/2-20 Drain Plug For Modulator Valve Plug?? blykins C4 Transmissions 1 03-16-2009 09:28 PM
Dumb question - oil drain plug homeinct Galaxie Pages 3 04-09-2008 05:30 AM
Gas Tank Drain Plug ? Gordo Galaxie Pages 10 11-11-2005 12:10 PM
leaky oil pan drain plug galaxiegray Galaxie Pages 4 08-26-2004 12:29 PM
drain plug on rear end??? Thordane65 All Ford Techboard 10 08-07-2004 03:21 PM

Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome