Frustrating Undiagnosed Clutch Problem

I bought this vehicle used a little while back. It is a 2009 Tacoma 4WD Extracab 2.7L 5 speed manual w/110,000 Mi.

I have an issue with the clutch which no one has been able to diagnose to date.

The clutch IS high, however, there seem to be some other anomalies:

1. Occasionally, the clutch will slip in 1st gear, although I can not get it to slip in any higher gears.

2. There is resistance to shifting, sometimes in all gears, but one circumstance that always encounters resistance is when putting it back into 1st from being stopped at a red light in neutral. In this instance, holding the clutch in for 5 seconds seems to help a little.

3. There seems to be quite a bit of play from when the clutch is first disengaged to when it is fully engaged. This means that on a 1-2 shift (especially on this shift) if the clutch is fully let out after it can be heard that a load has been transferred to the engine, it could still be a bit rough unless done with care.

4. The issue seems to improve a bit with a little highway driving.

I just bought this vehicle a little while ago, so I think most of any wear is from previous owners. I have driven with several mechanics who have said my clutch use should be okay for the vehicle.

Could this be something other than worn clutch plates?

Many mechanics have said no pedal height is necessary since hydraulic clutches automatically adjust themselves. Does this automatic adjustment ever fail?

Lastly, it there a diagram of this clutch, including linkage, available?

 

I would guess perhaps the slave cylinder. Possible moisture in the system or the slave cylinder could be going. Just a guess. As to the height of the peddle, no idea.

 

If the slave cylinder is going it will typically manifest as a fluid leak, and/or the clutch won't stay disengaged at a light.

I would suspect that it needs a clutch. If that's the case it could explain the difficulty switching gears. This difficulty is hard on the syncros in the transmission, and could cause them to wear out prematurely.

Hydraulic clutches aren't adjustable, or at least none I've seen.

The milage is certainly right for needing a clutch, especially if it's never had one.

 

I have basically the same truck as you, just an 07. It has over 180 K hard miles on the original clutch, but we did need to replace a leaking slave cylinder one time at around 130-140 K. I bought this truck at 40 K , and since the first day the clutch has had some type of slipping in first gear when taking off, especially on an incline. I still have no idea why it does it, and no matter how much you try to engage it correctly, it still makes a slipping noise for a second. It has never slipped or made noise in any other gear, and the disc seems to be in good shape ,I always figured it was just a trait of these 4 cylinders that had the Mexican made clutch in them.

 

Also remember that both the master cylinder and slave cylinder for the clutch can leak INTERNALLY which can manifest itself as difficult to get into gear, "creeping" after sitting in gear with the pedal on the floor, as well as pedal height issues. One option is to have someone in the cab while you look underneath. (Engine can be off) Have them press in the clutch to the floor while you watch the clutch arm. (the part that the slave cylinder pushes on the side of the transmission) If there is an internal leak in the master or slave, or if there is air in the system the arm will not remain where it moves to on the initial pressing of the clutch.

 

Well, I guess I will look at the hydraulics and if no problem is located will have to replace the clutch.

I still don't understand, though how both slipping and failure to disengage are both symptoms of the same problem. It seems to me like one is related to plate wear and another is related spring or throw out bearing problems.

Thus, we either have a theory that there are two seperate problems with the internals of the clutch both requiring disassembly and replacement; or we have a theory that there is a common denominator of a hydraulics issue.

 

no mechanic, but to me it seems like 1'st would be the LEAST likely gear to slip in.

get to idle, engaged, so rolling at a few mph, and floor it! what happens?

 

There is a distinct change you ARE dealing with two problems. The idea is to narrow down, and possibly eliminate one of them by checking the hydraulic system, which is an easy check.

Actually 1st is usually the FIRST gear you detect slipping. A very large amount of torque is being applied is on takeoff.

 

Clutch
Clutch System (For R155): Problem Symptoms Table
Clutch System (For R155F): Problem Symptoms Table
Clutch Pedal: Components, On-Vehicle Inspection
Clutch Pedal: Removal
Clutch Pedal: Installation
Clutch Master Cylinder: Components, Removal
Clutch Master Cylinder: Installation
Clutch Release Cylinder (For R155): Components, Removal
Clutch Release Cylinder (For R155): Disassembly, Reassembly, Installation
Clutch Release Cylinder (For R155F): Components, Removal
Clutch Release Cylinder (For R155F): Disassembly, Reassembly, Installation
Clutch Unit (For R155): Components, Removal, Inspection
Clutch Unit (For R155): Installation
Clutch Unit (For R155F): Components, Removal, Inspection
Clutch Unit (For R155F): Installation

 

There is 1/2" to 3/4" of free-play in the pedal.

I definitely plan to look at this.

I also wonder about jacking the vehicle up, unbolting the slave cylinder and clamping the release lever. If this results in no resistance going into 1st gear, we know it is not an issue in the clutch housing.

 

I followed some suggestions and took the clutch pedal mechanism apart. I did find that there was a lot of play in the throughbolt/rod. I ordered new bushings for the clutch pedal.

I was sent some info on a TSB for clutch pedal squeak noise. It suggested replacing pedal, bushing, and push rod clevis. This was for 05'-06' though and I am hoping I do not need to spend the money on replacement of all these parts just to fix the issue.


Still haven't figured out how to re-install the spring. Very frustrating. If it is installed before installing the through bolt, the throughbolt becomes near impossible to reinstall because there are two independent plates of steel the bolt must pass through on each side and these dis-align when put under spring tension. It also seems near impossible to compress it enough to put the spring on after the throughbolt is installed. I think they should have provided a pointed bolt for this purpose.