McLeod Hydraulic T.O. Bearing (Direct OE Replacement) Tremec TKX Transmission

Swapping a Tremec TKX five-speed into a muscle car, restomod or pro-touring build, or tired of a mechanical clutch linkage that binds and wears? The McLeod 1350 is the bolt-on hydraulic throwout bearing McLeod catalogs for the GM-pattern TKX. It takes the place of the transmission's front bearing retainer, so the release bearing and the slave piston become one part riding on the input shaft. Builders usually shop for it when a clutch will not fully release, the pedal feels inconsistent, or they want to get rid of a fork, pivot ball and Z-bar or cable entirely.

What the 1350 hydraulic bearing does on a TKX

The 1350 belongs to McLeod's 1300 series, which McLeod describes as hard-anodized billet aluminum replacements for the OEM bearing retainer, shipped with high-pressure stainless braided lines and elbow swivel fittings. A clutch master cylinder pushes brake fluid down an AN-4 line into the housing, the piston extends, and the bearing presses the pressure plate fingers. McLeod's instructions call it a constant running design: the bearing always touches the fingers but applies no load with the pedal up, which is why pedal height stays the same as the disc wears. The 1350 carries the adjustable-height piston, meant for an A dimension of 2.50 to 2.99 in. The fixed-piston version for a 2.31 to 2.49 in. A dimension is a different part number (1350-1), and a version packaged with a master cylinder is sold separately as well.

Symptoms this bearing addresses

• Clutch drag: the car creeps with the pedal down, or reverse grinds at a stop
• A squeal or chirp that only appears when the pedal is pressed
• Stiff, notchy or changing pedal feel from worn linkage, a stretched cable or a worn pivot ball
• Fluid disappearing from the clutch reservoir with no leak at the master, a sign an old internal slave is leaking
• A pedal that engages at a different height every time after a clutch change

Grinding on moving upshifts while the clutch releases fully points at gearbox synchronizers rather than the release system, so rule that out before you buy.

How to confirm before you buy: measure the A dimension

McLeod strongly recommends measuring before ordering, because the 1300 series comes in several heights. With the clutch installed and torqued, measure from the bellhousing face where the transmission seats to the tip of the pressure plate fingers, using a caliper that reads to two decimals. A ruler or tape is not accurate enough. If you read 2.50 to 2.99 in., the 1350 is the right piston. Between 2.31 and 2.49 in., you need the 1350-1. Over 3.00 in., McLeod sells a longer piston (139079). After the bearing is in hand, McLeod's dimensional sheet has you subtract the fully collapsed bearing height to get running clearance; you want .100 to .250 in. If you are still deciding between a clutch-side fix and a bigger gearbox job, our guide to manual vs. automatic transmission repair cost covers what each path usually runs.

Fitment

McLeod lists the 1350 as the 1300 series hydraulic bearing for the GM Tremec TKX 5-speed with the adjustable piston. That is the whole application: it is not a T56, TKO or Ford-pattern part, and it will not work with a counterweighted diaphragm pressure plate or a self-adjusting pressure plate such as the factory GM LS unit. If your TKX came from a kit or a non-GM bellhousing combination, send us the transmission tag, bellhousing part number and clutch you are running and we will confirm before it ships. For other manual-gearbox hard parts, browse our hard parts catalog, and if you are building a classic GM four-speed instead, the McLeod 1300-AG for the Auto Gear Muncie M23 is the same series for a different gearbox.

Install notes

• Collapse the bearing fully on the bench, then remove the TKX front retainer. McLeod singles out the 1350 here: the factory bearing race and shims behind the input collar must go back in, between the input shaft bearing and the McLeod housing.
• Align the relief in the lower housing the same way as the stock retainer, run a light bead of silicone on the mounting face, and keep the bleeder line at 12 o'clock.
• Sleeve both AN-4 lines with about 6 in. of slit rubber hose where they pass through the bellhousing so they cannot chafe, and route them away from the flywheel.
• The supply line from the master to the bearing is not included. McLeod's starting point is a 3/4 in. bore master with at least 1 in. of push rod stroke and a 6:1 pedal ratio.
• Use DOT 3 or DOT 4 brake fluid only. Silicone DOT 5 damages the seals. Bench bleed the master first, and leave the reservoir 1/4 to 1/2 in. below full, because the level rises as the clutch wears.

Pull and replace the pilot bearing while the transmission is out; an OEMTools pilot bearing puller makes that a quick job, and a universal clutch alignment tool kit keeps the disc centered while you torque the pressure plate.

Is the McLeod 1350 the right bearing for my Tremec TKX?

McLeod catalogs the 1350 for the GM-pattern Tremec TKX five-speed with an adjustable piston. It is the right choice if your measured A dimension is 2.50 to 2.99 in. Below that, the fixed-piston 1350-1 is the correct part.

What fluid goes in a McLeod hydraulic throwout bearing?

DOT 3 or DOT 4 brake fluid. McLeod warns against silicone DOT 5 fluid because it damages the O-rings and causes leaks.

Can I run it with a Centerforce or factory LS pressure plate?

No. McLeod states its hydraulic bearings do not work with counterweighted diaphragm pressure plates or self-adjusting pressure plates like the factory GM LS unit. Use a conventional non-adjusting pressure plate.

Do I need to reuse anything from the stock TKX retainer?

Yes. McLeod's instructions say the factory bearing race and shims that sit between the input collar and the input shaft bearing must be reinstalled between that bearing and the McLeod housing on 1350 installs.

What master cylinder should I pair with it?

McLeod recommends a 3/4 in. bore master cylinder with at least 1 in. of push rod stroke and a 6:1 pedal ratio as the balance of pedal effort and travel. The line from the master to the bearing is not included.

Why will it not build pressure after install?

The most common causes McLeod lists are a master cylinder that was not bench bled and a push rod that preloads the master piston with the pedal at rest. Adjust the rod so it has no tension at the top of pedal travel, then bleed again.

• Automatic vs. Manual Transmission Repair Cost: What to Actually Expect