Is my clutch slipping or is it something else?

2016 V6 6MT ACLB 80k miles w/ OVT 87 base tune
I changed over my spark plugs about one month ago after picking up some new ones at the dealership. The dealership sold me the one prong ones and the kind I took out had three prongs if that is at all relevant to the story.. I don't currently have a rough idle or anything but here is what I am experiencing:

Around the same time (I don't think it was before) of changing the spark plugs I noticed that when I put my foot on the gas well after my shift was completed the engine would race slightly. This is with my left foot completely off the clutch. It seems like I can make this happen at almost any speed or any gear (possibly with the exception of 1st) as long as the engine is under a heavier load either by going uphill or if I jam on the throttle in the flats. In otherwords, my tach would show increased RPM's (say 3k jumping to 3.4k) and the engine would sound that way but I would feel no 'push' from the rear end. I can duplicate this phenomenon on the flats or going up hill, haven't really tried it going down hill. I have never had to put the truck back in gear, and there doesn't seem to be any particular smell when it happens.

Thoughts? I can always try to make a video if it seems hard to understand. It is way different than the throttle delay issue I had before I flashed with OVTune, which at this point was over 1 year ago

 

That does sound like clutch slip. If you see the tach move more than the speedo and quickly decrease when you let off the high load, then that would confirm it.

I have had clutches slip in the past after a bit of abuse, like slipping when backing up a trailer. It can take a little bit to clean up the surfaces.

One thing to check is if there is the proper free play on the clutch pedal. If the master is riding the pedal, it can cause slip. There is clutch adjustment procedure in the 2016 SM that floats around here.

 

With the new plugs installed , you may be running into some serious throttle hang .
OV tune has a fix for the throttle hang with a manual transmission . Its a big thread
https://www.tacomaworld.com/threads...anual-transmission-engine-ecu-reflash.515734/

When you did the plugs , did you also remove the battery post and clean your throttle body ? That will help with throttle hang as well

 

Good point. Rev Hang is usually only a thing while the clutch is disengaged though. The tune greatly helps with shift smoothness though, esp over the 2016 through 2018 factory tunes.

 

I see he had the tune done but wasnt sure if the tune he installed was designed for the manual transmission .

In that case , his clutch is slipping . Hope he has warranty to 100K

 

The tune certainly adds a bunch of torque in the bottom end where the clutch would be slipping in higher gears.


I hope it is the pedal adjustment, esp with the careless nature that some folks have reported with the pedal TSB work.


I did have to adjust my clutch at about 25k or so because it started clicking with too much gap between the end of the M/C stroke and the resting position of the pedal.

 

As the clutch disc wears down ,the release bearing gets closer to the pressure plate which in turn should have removed the free play in the pedal .
You are probably correct . I bet ya he has a partially applied clutch and doesnt know it . A very very common problem not only with 3rd gen but 2nd gen too.
I like the accumulator delete as well . Makes a huge difference in the way the clutch applies as well as releases
https://www.tacomaworld.com/threads/mt-accumulator-delete-mod-adm-and-bs-thread.568303/

 

I do enjoy that with hydraulic clutches.


Yes! The ADM is huge.


And, thanks again for putting together the 2016 SM.

 

Doubt clutch is going to be covered by warranty. Would you ask for new tires if they wore out under warranty period?

 

I can do the clutch replacement.. there is little I haven’t done to the truck so far. Hard to find an in stock replacement kit though Rockauto has none. Autozone has none. Napa has none. Or Willy has none. Yes has only stage 3 which I am not interested in.

 

I did disconnect the negative battery terminal when doing plugs, did clean the throttle body so I wouldn’t get any dirt in the innards when I was working... I’ve been using OVT and the cable as well as the Toyota software to update my firmware and tune for about a year. It is the right tune for my truck. The blip in throttle increase only happens when the clutch is engaged and I put good pressure on the gas pedal. Strangely enough Inhave the ADM mod and 2Lo sitting in my garage, haven’t done them yet...

 

If you do the clutch, it is a perfect time to do the ADM. Sucks though.

 

There is the URD Stage 2, but it is OOS and there have been a couple reports with noise issues on the center collar and / or wavy washer. Also, there might be a batch issue with the OEM-only throwout bearing.

@su.brat and @b3itz will have those details.

 

I feel like I got the last stage 2 clutch kit URD had on the shelf lol. I paired it with the heavy flywheel
I've had some noise issues with the adapter ring in the center of the pressure plate on the stage 2 kit. It didn't happen until about 3k miles in, and after about a thousand miles of chirping or whurring when the clutch was to the floor, it magically stopped.
Other than that, I'm extremely pleased with this clutch.
Honestly, I don't think I'd hesitate and I'd grab the stage 3 if it's in stock, but that's just me.

I did the clutch job FIRST, then ADM after to isolate any issues.
Besides the noise, all good here.

Literally like no one locally carries a clutch. Only the dealer.

 

Hmmmm actually, I have a clicking sound when my clutch is not to the floor. Almost like a clunking. Is this the culprit? I don't know jack about adjusting this new doohickey you speak of

 

If it is clicking as soon as you put pressure on the pedal, the yes.

If it is clicking as the pedal moves, then it is the spring and needs some disk brake grease smeared in there.

The adjustment is easy. Just follow the SM. I think @MOC221_ has posted the specific section a bunch of times.

 

I would really like to see Ben try and adjust the clutch before replacing the clutch .

 

The sooner he adjusts the clutch , the better the results will be .
Thanks tonered
I forgot how bad these clutches function as they age . Such a horrible design !

 

You're welcome!

Yes. It could have been simpler and better. Still, with two or three TSBs, they still didn't fix it the proper way.

 

I don't get what adjustment you're talking about at all. So the release bearing is shoved against the pressure plate fingers 100% of the time regardless of a brand new clutch assembly or a badly worn out one. If any wear changes its physical position that only affects the parking position of the piston in the slave cylinder. Lets say the master cylinder is adjusted in such a manner that it displaces enough fluid to move the piston in the slave cylinder 1/2" that will never change unless you physically change that in the cab. You will have that 1/2" of travel from wherever that piston in the slave parks. Whatever adjustment you have on the push rod for the master cylinder from day one on a new clutch will be the same when its totally worn out. It's not a closed system.