I have an occasional quirk with my pickup. It occurs about 10 percent of time engaging clutch from stopped. It does not happen during shifting gears up or down while moving.
The whole vehicle shudders and it doesn't want to move. Revving the accelerator seems to lead to proper engagement of the clutch.
When I took it to my local shop about four months ago to replace the leaky water pump, I asked the mechanic to evaluate my clutch problem. His opinion was that the clutch might be warped.
When a coworker changed my clutch about 150K miles ago, I am sure he didn't replace any cylinders, forks, or anything else.
Do I need a new clutch? Or, might it be an adjustment situation?

 

Wouldn't hurt to bleed your hydraulics but it sounds like it could be slipping. Take it out and drive uphill at like 45 mph in 4th or 5th (low rpm) then go full throttle it and see what happens.

Where did you get the replacement clutch? If it wasn't Aisin or a reputable brand I would be glad you got 150k out of it. Never shop at the box stores.

There is no reason to replace the fork or the hydraulics when replacing a clutch - hydraulics especially, those can be done easily without pulling the transmission.

 

150K miles on a clutch? Way past time for a replacement. 2X on getting an Aisin or reputable brand clutch, because the job is hard enough (or expensive enough if you have it done!) without having to do it twice to pull out sub-par parts that failed prematurely.

 

It's my second clutch! I don't know the brand. My coworker mechanic had an account at Advance.
There is never any slippage after I get moving.

 

Op says: revving the engine engages the clutch.

That sounds mighty jerky to me. Shock loads break things.

It also means the clutch is sticking mid clutch pedal travel.

Pushing the clutch uses hydro force to move the clutch away from the flywheel. Letting it go makes springs spring back pushing liquid the other way.

Get the toyota clutch master and slave rebuild kit. Rebuild master and slave.
Bleed.

If that doesn't work, replace clutch and pilot bearing.
Could the pilot bearing be sticking in it's travel?

 

What I mean by revving is: When the pickup shudders at clutch engagement, the RPM dips to about 500, nearly stalls, sometimes stalls. Then I rev the engine and re-engage the clutch at 1000-1500 RPM. Then it moves OK.

 

Not likely an adjustment. 150,000 miles?...you got your money's worth. Clutch warped? Maybe. Has it ever been overheated, as in excessive slipping from heavy towing, or some ignorant driver holding on a hill by repeatedly slippinmg the clutch? Glazed or checked/craccked flywheel or pressure plate? Could be, I suppose. In any case you need a ""competent" mechanic to evaluate. That might mean taking stuff apart. Yes, that will cost. Maybe you can do-it-yourself?

Anecdote: The original clutch on my '89 2wd four-banger started slipping @ 172,000 miles. I didn't notice it until I had to pick up a motorcycle in hilly San Francisco. It had survived a teenage boy learning to drive and "hey Dad, can I borrow the pickup?" too.

 

For what it’s worth, the 2WD trucks are EXTREMELY easy to do clutch work on. Probably one of the easiest vehicles out there. I’d just tear it down and see what’s wrong.

 

I might should do it myself. I might not be able to tell what's wrong.
I will look for YouTube instruction video.

I watched. Replacement steps don't look too complicated, but I don't have access to a lift.

 

It doesn't slip on grades, and I don't know that it has overheated.
Sory, I don't know how all the parts work.
Thanks.