1998 5-Speed Help, Engaging Clutch smoothly

[theultimatehero]

Hi folks!

I have to admit this is a somewhat embarrasing post. I enjoy driving manual transmission vehicles and I always have since my first car 7 years ago. I have always driven cars and my 4runner is the first "truck" type vehicle I have ever owned or driven for that matter, with a 5-speed.

The problem I have is with engaging the clutch and starting from a dead stop smoothly, without jittering, vibrating and rattling my way into engagement and subsequently moving. I can't figure this thing out and I am trying to figure out if the issues I have with this are related to driver error or possibly issues with the vehicle. I have never had such a tough time operating a clutch.

Here is the lowdown on the 4runner. Its a 1998 5-speed SR5 with 4WD. It has about 220k Miles on it. I have no idea what the condition is of the clutch, but I have personally replaced the clutch master and slave cylinder. This was due to the master failing and causing my clutch to literally cease functioning, I don't believe it is related to this issue. This issue of engaging roughly was apparent before doing the cylinders.

I have tried all kinds of methods to start the truck. If I try to slowly engage the clutch from idle I can get the clutch to engage at a crawl then accelerate from there. That can be done smoothly, but it is extremely slow and annoying in traffic. I've tried holding revs at around 1-1.5k and releasing the clutch (which works in most cars i've driven) but this is where the stuttering, jittering, jerking etc. happens the worst. So my usual method is to give the truck some gas and slightly release the clutch around 1.5-2kk then allow the revs to drop and meet the speed of the vehicle around 1k. This is off and on, sometimes smooth but often its is really jerky.

The problem seems to be worse when the vehicle is cold. Sometimes it improves with more driving, but I can't figure out if that is due to my feel for the truck or if some components are literally working differently.

Does anyone have some advice for me? Is there some kind of wear items that could be causing this? Clutch? Engine mounts? Worn suspension bushings? I know I need shocks badly, could that do anything to help?

 

[scrap metal]

Worn transmission mounts (and engine mounts) can cause a rocking back and forth which translates to jerking motions.

Are the revs actually jerking up and down or just the actual truck? I have a 2000 5 speed and clutch engages smoothly.

Also, another thing to consider is what clutch you have installed. Is it factory? I guess technically if a racing clutch was put in (which I doubt) it would be hard to engage smoothly

 

[Paperjam]

One of your clutch springs sounds broken, for it to buck and jump around like that. There is also another spring called a marcel spring in the disc itself to absorb the shock of the pressure plate engagement, if that is flat from overheating it makes for a rough engagement as well. Those springs are there to smooth the engagement and prevent this condition. Also try bleeding your clutch system again, there are a few ways to do it but a little air in the system can make driving the thing a pain.

Since you have an unknown clutch I would consider dropping the trans and inspecting everything.

My 5 speed is quite easy to drive for reference

Engine mounts are possible but you would also notice a bang sound under hard acceleration or deceleration. Shocks are a no

 

[clemson4r]

My vote is on hot spots on the pressure plate and flywheel. If the previous owner revved to 3-4k and rode the clutch from a stop that can easily cause hot spots. Mine was in similar shape when I got it, I replaced the clutch, flywheel, TO bearing, etc and the problem was solved. It was easy to see the discoloration on both the pressure plate and the flywheel when I did this.

Max

 

[theultimatehero]

Worn transmission mounts (and engine mounts) can cause a rocking back and forth which translates to jerking motions.

Are the revs actually jerking up and down or just the actual truck? I have a 2000 5 speed and clutch engages smoothly.

Also, another thing to consider is what clutch you have installed. Is it factory? I guess technically if a racing clutch was put in (which I doubt) it would be hard to engage smoothly

The truck itself. If I have tools or something in the back, everything is clattering around whenever I get moving from stopped.

I have driven some pretty touchy "race" style clutches in cars, thats not what this feels like. Those clutches grab and go like a lightswitch. This thing stutters and bucks like a wild donkey.

One of your clutch springs sounds broken, for it to buck and jump around like that. There is also another spring called a marcel spring in the disc itself to absorb the shock of the pressure plate engagement, if that is flat from overheating it makes for a rough engagement as well. Those springs are there to smooth the engagement and prevent this condition. Also try bleeding your clutch system again, there are a few ways to do it but a little air in the system can make driving the thing a pain.

Since you have an unknown clutch I would consider dropping the trans and inspecting everything.

My 5 speed is quite easy to drive for reference

Engine mounts are possible but you would also notice a bang sound under hard acceleration or deceleration. Shocks are a no

Yea I've been considering the clutch springs being the culprit. It sounds more and more likely I would have to pull the transmission to see what's going wrong in there.

My vote is on hot spots on the pressure plate and flywheel. If the previous owner revved to 3-4k and rode the clutch from a stop that can easily cause hot spots. Mine was in similar shape when I got it, I replaced the clutch, flywheel, TO bearing, etc and the problem was solved. It was easy to see the discoloration on both the pressure plate and the flywheel when I did this.

Max

Sounds like similar stuff to clutch springs. I am beginning to think the clutch is not so healthy.

Thanks for all of the advice guys. Unfortunately I am in the middle of an engine swap for my car, so I can't get going on this right away. I will try my best to update this thread when I get some answers.