Intermitent clutch slippage

Well, I have been having some clutch slippage issues lately, so I thought I would bounce it off of you guys.

I have an '09 Reg cab Prerunner with a little over 9500 miles on it. A few weeks ago I started noticing that I would have some clutch slippage in 4th and 5th gear. Now, I know at this point some of you are thinking "Holy $hit how can you blow through a clutch in less than 10k miles". Well, I don't think that its the clutch that is causing the slippage, I think that something is causing the clutch to momentarily disengage. It has occured during differing conditions, but the most repeatable goes like this:

I'm driving down the road doing 45ish and in 4th gear. I decide that I want to accelerate, say to pass someone. I'll step on the gas, not matted but close. The RPM and speed will start to climb normally. As it gets to around 3000 RPM (typically, it varies) it will jump about 700 RPM, but maintain a steady acceleration. It feels like when a torque converter changes gears on an automatic. I know I know, sounds like a worn clutch, but here is where it gets weird. Almost immediately after the RPM spikes, it will drop right back to where it was for a few seconds and then spike again. If you keep your foot on the gas the tach will just sit there and bounce. It almost feels like something is causing the clutch to momentarily disengage and the reingage, wash, rinse, repeat.

I took it in to the dealer to check it out, and they couldn't replicate it. So I went in and drove it for the tech and got it to do it. It didn't do it as bad, but it did do it. They called me last night and told me that they couldn't get any of there techs to replicate it, so they don't think that there is anything wrong with it. Obviously, this makes me think that they are a bunch of retards. Being that the truck doesn't even have 10k miles on it yet, I find this very frustrating. I guess I'll have a piece of paper now that at least says that I brought it in to have it looked at for later down the road. If it continues to occur or gets worse, I'll definately bring it back in, but it won't be to that dealer. I'm sick of dealing with them. I have two Toyota's (04 Matrix), neither of which I purchased from them because their sales dept is a bunch of pricks too.

I know this is lengthy, and kind of half problem, half rant, but what do you guys think? Hopefully some of you Toyota techs will weigh in on this too.

 

I had my clutch assembly do something similar under those same circumstances but I couldn't press my pedal in at first and then it was making this crazy banging noise. A few miles down the road and it was fine. It felt like the clutch disc had ripped apart and then reseated itself. I had it to the dealer twice and they say nothings wrong. I've put over 12k on the truck since this happened and it's seems OK but...?
Now I find this TSB and it really makes me wonder.

 

OP you state you feel this at approx 3000rpm with an increase of 700rpm during moderate loads of the engine.

To me this indicates nomal operation of the VVTi switching modes as the dealer also found nothing wrong.

 

Without a difference in pedal press, and assuming a flat surface, the tach should not bounce (engage, disengage, engage...) for normal VVTi switching.

 

That's kind of what I figured too. There is no surging or jerking of the vehicle either while the tach is bouncing around. Unless I'm wrong, I was under the assumption that a manual transmission is a direct mechanical connection from the engine to the rear wheels, and any fluctuation will be transmitted through the whole system, except when the clutch is disengaged or is in the process of being disengaged (partial contact).

And with respect to the VVTi, I wouldn't expect it to switch on and off under constant pedal pressure. My Matrix also has VVTi (automatic) and in 142k miles it has never done that.

 

mine does it too...and it really likes to do it in 4th. If you keep your foot in it and let it keep slipping, you'll start smelling the clutch burning. But other times it catches fine.

 

I'm just really worried that I'm doing damage to the clutch. The dealer didn't even want to look at it because they couldn't replicate it.

 

I have a similar issue. Mine is at 2500 rpm during heavy load, like up a slight hill. Rpm does not jump around but the truck does have a bogging feeling as I am slowly increasing my speed past the 2500 rpm.

 

I have 09 4cyl 4wd Mt tacoma... 20,000 miles

I too notice the 4 and fifth gear slip any time after 2000 rpm... It seems to be worse when its cold outside, say below 20F. There is noway its the VVT . remember the a manual trans and clutch don't have any slip because it direct drive... Plus when you let off the gas it will re catch..

I haven went to the dealer yet because I figure they are swamped already with the recall for the runaway corolla's

 

Considering I drive the 4 cyl prerunner myself, I can tell you that the 4 banger should not be jumping anywhere near 700 rpm when you smash it in 4th gear. You should have a nice steady increase in rpm, and at that, it takes quite some time to gain 700 rpm in 4th gear out of that 4 cylinder engine.


You have a problem there. I have never experienced what you are saying while driving the taco.

 

I hope the dealer can cover it.. IF not I'll put a better clutch in.... but thats kinda the point of having an 09, not having to wrench on it!

 

I love this thread today!!! I have an 08 FJC and was searching for more info on clutch for our 6/MTs.

 

there is no way the VVTi would cause the engine to jump 700 rpm. assumming normal engine/clutch/trasmission/differnital operations, the only way the engine can jump 700 rpm is if the car speeds up. if the clutch isn't in, the whole thing is like one big solid unit....if everything is working correctly.