So a year ago I bought a 1985 4runner Automatic and the guy tells me he thinks the motor bearings are bad. The body, chassis, and interior are perfect. Turns out the noise he heard was a flex plate that cracked. I had that replaced and just the other day I spun it out again. It is total flexplate fubar. My technician is willing at no cost to replace it under warranty but I am not sure that will fix the problem. My technician is very OEM stock happy FSM neurotic.


The truck runs great, transmission shifts smooth, and I am not sure what can cause this 2nd failure. Technically it happened now twice in a year with the original. The only odd thing I notice is an intermittent rattle when changing from 3rd to 4th gear under load ( like up a hill). Also, I can't be sure but maybe a tad loss of power in 4th after it shifts into that gear. But no shutter, no hard shifts, or anything?


The second flexplate was put in to exacting FSM specifications and a new starter (Denso)was included at the time. There were no cracks in the plate up until the second break because I checked it regularly. It went fubar changing between 2nd and 3rd gear.


The truck is a 205k vehicle with no work needed except timing chain drivers side guide replaced and the original flexplate.


I am thinking about dropping a new motor and tranny in it so I do not chase demons and end up spending more and not fixing problems.


Has anyone here had flexplate issues like this and resolve their issue by finding some issue with thrust bearing, torque converter, or gearbox etc.???

Any thoughts, ideas, or general discussion would be greatly appreciated!

 

109 views and not one response?


How about at least one of you put feathers on your head and dance around a fire chanting?

 

My only guess is at sometime were the wrong bolts installed?/

Correct bolts used in the torque converter ??

These are special and different then fly wheel bolts.

Just what brand flexplate are you buying ??

I am not a Auto Transmission person.

Something is causing a out of balance condition causing enough vibration to start the crack .

Bolts not torqued even for what ever reason one to tight or loose

Pictures would be great of the failed ones.

 

Any vibrations? I just trying to think what would cause it to crack. I too wonder if it is correct bolts or something similar.

 

I am tending to think it is the drive shaft itself. The engine is 210k. The mechanic I use does not deviate from OEM parts and is very precise on work. He loves the old Toyotas and has a lot of experience with them.


The reason I think it is the drive shaft is we increased horsepower by eliminating the cat and a better higher flow muffler. 4 days later she broke in a simple smooth shift from 2nd to 3rd. The original flexplate was the stock one so It would be the factory bolts on converter. The technician definitely checked everything regarding alignment, specifications per FSM, and whatever else while in there.


It is a pain because the tranny is super smooth no shutters, good shifts, and tight. Other then the occasional idle issue the engine is powerful, smooth, and starts every time.


The clue is the "rattle" intermittingly between 3rd and 4th under load. I am just thinking the engine driveshaft, bearings, thrust bearing, and everything else must have crossed that line out of spec. If it were a 5 speed I may get away with it but the auto maybe not so much...


I have the tech quoting a new engine and tranny. He is good and helpful I should get out under 5,000. Costing that over 3 years is only 130ish per month, over 4 105ish per month. I just wonder what the value would be after that work is complete. Interior is perfect flawless, no rust at all on chassis, and light dings here and there on body..


I just do not want to chase 1000 dollar demons when I could just get it redone from scratch

 

I replaced some u-joints a year or so ago and didn't have any problems afterwards. About 6 months after replacement I started having a rumble and slight vibration. Since I had new u-joints I figured it had to be either the transmission, transfer case or rear end. I swapped the rear end and still had the issue, so then I swapped out the transmission and same thing. I had another drive shaft and swapped it out and that fixed. A lot of work for u-joints.

I had checked the driveshaft with the rear end up on jacks and it ran great with no signs of problems. But with the rear end on jacks it isn't under a load. I can swap out u-joints but I pull the driveshaft and will have a mechanic that has a press to do them.

 

Thanks Terrys87!

 

Any luck or updates?

 

After putting feathers on my head and dancing around the fire of a burning J*ep.

The great Toyota Gods

Ask???


If your mechanic is as good as you think .

If you go with his idea will it be able to be done in 6 months ??

Maybe even longer ??

I think your putting way to much faith but that is me.

What does he think is causing your problem??

As to what your truck is worth only what someone might pay

 

Terry no updates but the general consensus is the drive shaft/thrust bearing has play and it moves forward and back. That comes from a 12 year Toyota Tech (my friend), a 25 year Toyota tech (A good friend), and my technician ( known for a long time). When I pull the trigger on what I am going to do we will verify that when swapping out motors.


Wyoming9:


I have known the guy (my mechanic) since 1990 and yes he is very good. On top of that he is honest as well. He also has a brother in town who is also very good. Both these guys have been building cars and racing for a long time. My technician owned several Toyotas w/22RE from Celica's to 4runners so he is familiar with them.


As for "his idea" not sure what you mean? When I bought the truck I thought I needed to replace the engine to start with, as the original owner said the motor bearings were shot. But the flexplate was cracked when I got it and it made a noise which we felt the original owner thought was the motor. So for about 800 dollars we have kept it running for almost a year.


So I am initiating the full motor tranny replacement both new OEM. That's why I bought the truck was to restore it to stock condition. Once we order the parts it'll take him no more the 3-4 days.


Here in the PNW these things go for outrageous $$$. I had two people try to offer me $$$ to buy in the 6000 range already. Interior perfect, body excellent, No rust, just high mileage...And now the result this issue. All machines need some love time to time :0 Its time...