Clutch slipping or something else?

[RufusTheDufus]

I have an 84 JDM Hilux with the 2L diesel. Seems like maybe the clutch is starting to slip but it only happens in the 3rd to 4th gear transition when I'm accelerating pulling a 800 pound snowmobile trailer/sled combo. It's really strange. It doesn't appear to slip with no load, even when going up a good incline.

The engine RPMs will increase in 4th gear after the shift without a corresponding increase in MPH. Truck as 33s on it which could be contributing the the problem. (Oversized tires will drop the engine RPMs more between shifts.)

Before I yank the engine to inspect the clutch I figured I'd ask here if there's anything in the trans that could go bad and cause this behavior? I think not, it shifts smoothly and doesn't ever pop out of gear or grind in any way.

 

[ferg]

Sounds like clutch to me. Do you really need to pull the engine for that? Seems it would be easier to drop the trans.

 

[pappy]

Sounds like clutch to me. Do you really need to pull the engine for that? Seems it would be easier to drop the trans.

This ...

 

[Bogo]

Much easier to drop the transmission. When I did mine I made 4 solid wood ramps out of 4 layers of 2x8s, and drove the truck up on them. You'll need to support the back of the engine. I used a 2x4 that spanned from fender to fender with a threaded rod, and hooked the rear engine lift point. I could then support the rear of the engine, and use the nut on the threaded rod to adjust how high the rear of the engine was. You'll need some long extensions and swivels to access the bolts on top of the bell housing.

 

[RufusTheDufus]

I was just under there yesterday changing fluids and greasing universals. From under the vehicle it looks easier to yank the engine than drop the trans. The 5 speed with the transfer case looks quite large and awkward. (I do have a hydraulic transmission jack.)

I'll read the FSM to see what's involved in dropping the trans vs. pulling the engine.

Is there enough room to pull the flywheel off the engine with it bolted in place? Seems like there should be enough room with the trans removed. I'm just thinking if I need to have it resurfaced or replace seals,etc., are these things possible with the engine in the truck?

 

[PAToyota]

Less to disconnect on the trans/t-case than the engine. Also easier to lower the trans/t-case to the ground than pull the engine up and over the front.

 

[KLF]

There's no way I'd pull the engine instead of dropping the tranny.

Much easier to drop the transmission. When I did mine I made 4 solid wood ramps out of 4 layers of 2x8s, and drove the truck up on them.

Yes, drive the truck up on ramps first.

You'll need to support the back of the engine.

No you don't.

The guy I bought my truck from used to be a Toyota tech back in the 90's, he would do 2-3 clutches a day. He taught me a trick that makes things so much easier. Unbolt the exhaust from the manifold (long extension, 14mm swivel socket). Unbolt just the FRONT of the rear driveshaft, leave the rear end connected to the transfer, let it hang (remove the back of the swaybar if you have one). Unbolt the front end of the rear driveshaft, drop it on the floor, swing it out of the way. While you're doing all this, have someone work in the cab, remove the console/boot, pull the shifters out. Put a GOOD tranny jack under the tranny/transfer, unbolt and remove the crossmember, lower the tranny down. Yes the engine will rotate on the mounts and the tranny will tilt. This will make it sooooo much easier to reach the upper bellhousing bolts (long extension and swivel sockets again), the starter, and the slave.

We did 2 clutches in one day on the floor of his garage (no lift, no special tools), less than 8 hours to do both of them. I've since used this method many times, it works great.

Yes you can absolutely pull the flywheel off with the tranny out. Best practice is get a spare one, have it surfaced and ready to go ahead of time. Always always always replace the rear main seal!

 

[Mudder]

I believe I've copied most of what KLF suggested. The only thing I did different wad drop the tranny down and get the top two bolts out first.

 

[RufusTheDufus]

Thanks for all the feedback. I'm not sure if I'll need to put the truck up on ramps. It sits on 33s with a 2.5" lift. If I put it on ramps I'll need to build a platform for the tranny jack.