t45 transmission How far does the clutch fork needs to travel to fully engage/disengage

[SethG]

Hi all! I'm new here. Just acquired a frankencar with a Tremec T-45 from a 1998 Mustang Cobra swap. And I'm struggling to solve a shifting issue. I see lots of information on the travel distance needed for a t5 transmission, but I can't find it for a t45. Trying to figure out what size master cylinder I need. Anyone know?

Just for the curious, here's the car
my car is using a wilwood 7/8" pull type slave, but still have the original 5/8" master. I'm almost positive I'm not getting enough travel. How much I need... I just don't know.

Thank you so much in advance. My car knowledge for 70's VW's is strong, but beyond that I'm pretty lost.

 

[Noobz347]

<<< Bangs his head on the Mustang sign hanging over the door and moves thread to [Other Auto Tech].

 

[SethG]

<<< Bangs his head on the Mustang sign hanging over the door and moves thread to [Other Auto Tech].

Truly sorry. I read your intro information. Clearly got it wrong. Appreciate you moving me to the correct spot. And apologies for taking up your time.

 

[General karthief]

You prolly need to find out what size master cylinder is used with the stock slave cylinder and match it to your setup.

 

[SethG]

Yeah, I’ve done that. But the geometry on my setup is different. And I could really use the distance needed to engage/disengage.
I’ve done the math, but the way it connects to the fork is different- so it’s not a proper match. On my hunt, the T5 has people documenting the travel needs to be at least 1”. But I can’t find it for the t45 anywhere. And I’ve spend hours searching before I reached out here.

 

[Noobz347]

That's because there isn't one. It varies depending on your setup.

The clutch throwout bearing length for a T45 transmission isn't a fixed value; it depends on the specific clutch setup, pressure plate, and bellhousing configuration. Unlike some transmissions with standardized measurements, the T45 requires precise adjustment based on the clutch assembly.

Typically, the throwout bearing travel distance needed to fully engage/disengage the clutch is around 0.800 inches for high-performance hydraulic release bearings, with a recommended gap of 0.150 inches for single-disc clutches or 0.200 inches for dual-disc setups. However, no direct measurement for the T45 throwout bearing length is provided in standard specs, as it varies by application (e.g., 1996-2001 Mustang GT or Cobra with a 10.5" or 11" clutch).




To determine the exact length:

Measure the "A" dimension: Distance from the bellhousing flange to the pressure plate fingers (e.g., 2.375 inches in a T56 setup, which shares similarities with the T45).

Measure the "B" dimension: Distance from the transmission mounting flange to the front of the throwout bearing.

Calculate clearance: Subtract "B" from "A" and adjust to achieve 0.100-0.150 inches of clearance (e.g., McLeod recommends 0.135 inches for a T56, applicable to T45).

For a 1998 Mustang Cobra T45, users report issues with insufficient travel using a 5/8" master cylinder, suggesting a 7/8" Wilwood pull-type slave but without specifying exact bearing length. Hydraulic throwout bearings, like McLeod’s 1300-Series, allow adjustable engagement, which is critical for T45 setups.

 

[SethG]

Thank you so much for your reply! Really appreciate your time and expertise. That's really useful info.

 

[Noobz347]

Hope it helps. I'm not an expert in this area but I know where a lot of the bodies are buried and the McCleod site helped a lot.