idid this a few months ago.
i have the t3650. i used mobil 1 atf and have yet to have a problem.
I filled it up with a hand pump while it was on jacks becuase knowing my luck id drop the fluid in my cars interior and **** it up if i went through the shifter.
Trans Fluid Swap
For comparison’s sake here’s how a few of the transmissions compare:
All of the above transmission pre-2005 had a direct mounted shifter. This means the shifter is mounted directly on top of the transmission. For 2005, Ford moved the shifter to obtain a more comfortable shifting position (and for packaging) so the shifter is now connected to the transmission via a link arm.To demonstrate how to change the fluid, we’ll be using our Project Hollow Point (link), a 2001 Bullitt with the T-3650 transmission. From the factory, these transmissions came with Mobil 1 factory fill, but since the cold shifting was so bad we decided to try something better.First we’ll talk about how to change the fluid in the transmission and a few details about that fairly simple swap then I’ll have some details about problems with the T-3650 transmission.To change the fluid, the first thing to do is gather a few basic tools you’ll need to complete the job. Here’s a list of what you’ll want to have:
1. 3/8” ratchet (I prefer to use a flex-head ratchet as it makes the angles a little easier to deal with)
2. 3/8” extension, 3” long
3. 4qts. Of new fluid
4. drain pan
5. Jack and jack stands
6. Hand pump
Hand PumpFor the fluid, I highly recommend Royal Purple Syncromax fluid for every transmission listed above.
With any of them, it will reduce friction and smooth the shifting noticeably. Our Bullitt has the T-3650 and shifting to 2nd below 40 degrees Fahrenheit was nearly impossible with the factory fill Mobil 1. Would the Royal Purple help? Let’s swap the fluid and see…
Once all of the materials are gathered, the next thing we did was jack up the front of the car to gain access to the transmission area. It helps here to place the jackstands at the back of the front subframe, or at the front of the subframe connector if so equipped (NOTE: factory subframe connectors are NOT acceptable jacking locations).Now if you look at the bottom of the transmission towards the front, you’ll see the drain plug. It has “DRAIN” stamped into the transmission next to it.
Position the drain pan under the plug, then remove the plug using the 3” extension on the 3/8” ratchet. Let the fluid drain completely.Clean off the plug
When the fluid is done draining, clean the area around the drain hole and reinstall the drain plug.Now look at the driver’s side of the transmission towards the rear about ¾ of the way up and you’ll see the fill plug.
Using the 3/8” ratchet again, remove the fill plug. Clean the fill plug and have it within easy reach to put it back in when needed. Assemble the hand pump and fish the output end into the fill hole. Slowly fill the transmission with the new fluid until it just begins to runs back out of the hole then reinstall the fill plug. Now you’re done.By switching to the Royal Purple fluid, our Project Bullitt gained the ability actually shift gears when the temperature outside is below 50 degrees. We’ve accomplished in 15 minutes what Ford couldn’t do in several trips back to the dealer under warranty.The following information is regarding the T-3650 transmission specifically, but the fluid swap procedure and general information applies to all years and transmissions. The demonstration swap was performed on our Project Hollow Point.In 2001 when Ford switched to the T-3650 transmission, it was a great change. The 3650 is very strong and can take some pretty serious abuse, well past the point of where the old T-45 would have failed. The downside on the swap was that the 3650 has a few problems of its own.
Most owners have at least one of the following problems:
i have the t3650. i used mobil 1 atf and have yet to have a problem.
I filled it up with a hand pump while it was on jacks becuase knowing my luck id drop the fluid in my cars interior and **** it up if i went through the shifter.
Trans Fluid Swap
Over the years, Mustang transmissions have been fairly consistant and have gotten better with time. As a basic guideline, here’s the breakdown of what transmissions came from Ford:
Mustang Model
Transmission5.0 L (up to 1995)
Borg-Warner T-5 5-speed1995 Cobra R
TTC 3650 5-speed1996-mid 2001 GT and 1996-1999 Cobra
TTC T45 5-speed2000 Cobra R, 2003-2004 Cobra
TTC T-56 six speedMid 2001-2004 GT, 2001 Cobra, 2001 Bullitt, Mach 1
TTC T-3650 5-speedAll 1994-2004 V6
BW/TTC T-5 5-speed, but a different model T-5 than the v82005 GT
TTC T-3650 with remote shifter2005 V6
TTC T-5 5-speed with remote shifterFor comparison’s sake here’s how a few of the transmissions compare:
03-04 Cobra T56 gear ratios
T3650 gear ratios
2.66, 1.78, 1.30, 1.00, .8, .63
3.38, 2.00, 1.32, 1.00, .62
T3650 gear ratios
2.66, 1.78, 1.30, 1.00, .8, .63
3.38, 2.00, 1.32, 1.00, .62
All of the above transmission pre-2005 had a direct mounted shifter. This means the shifter is mounted directly on top of the transmission. For 2005, Ford moved the shifter to obtain a more comfortable shifting position (and for packaging) so the shifter is now connected to the transmission via a link arm.To demonstrate how to change the fluid, we’ll be using our Project Hollow Point (link), a 2001 Bullitt with the T-3650 transmission. From the factory, these transmissions came with Mobil 1 factory fill, but since the cold shifting was so bad we decided to try something better.First we’ll talk about how to change the fluid in the transmission and a few details about that fairly simple swap then I’ll have some details about problems with the T-3650 transmission.To change the fluid, the first thing to do is gather a few basic tools you’ll need to complete the job. Here’s a list of what you’ll want to have:
1. 3/8” ratchet (I prefer to use a flex-head ratchet as it makes the angles a little easier to deal with)
2. 3/8” extension, 3” long
3. 4qts. Of new fluid
4. drain pan
5. Jack and jack stands
6. Hand pump
Hand Pump
With any of them, it will reduce friction and smooth the shifting noticeably. Our Bullitt has the T-3650 and shifting to 2nd below 40 degrees Fahrenheit was nearly impossible with the factory fill Mobil 1. Would the Royal Purple help? Let’s swap the fluid and see…
Most owners have at least one of the following problems:
- Excessive transmission noise (whine)
- 1st to 2nd gear clash (more noticeable when cold)
- Drivetrain “clunking” (various times, normally when clutch pedal is pressed when car is not moving)
