This might be it for me and my T4R...

[Nelsonmd]

This might be it for me and my T4R... PSYCH!

So I went to pick up the GF at the airport this morning, and on my way I heard a solid clunking followed by no acceleration. I coasted to a spot with a wide shoulder and pulled over. Once I turned the engine off, it wouldn't even turn over anymore. It sounded like it was struggling to turn over, but it wouldn't.

I got it towed home and now I have to go try to assess the damage. I suspect this might be it though. This thing has so much rust that I am not feeling like it is worth investing much into. All the stuff that I have cleaned and POR-15'd over the years has rusted again and I feel like I'd be starting over with the rust fight.

If any of you have some ideas on how to diagnose this, I'd love to hear it. I'd say I think the tranny failed, but then I don't know why the engine wouldn't start. So then I'd say it was the engine, but it kept running and still rev'd after the clunk and loss of drive. I didn't see any puddles of fluid left on the road when it happened, and there was no leak whatsoever when I was stopped.

Any thoughts?

If it's toast, then I'm not sure I'd get another 4Runner unless I could find a really good deal on it. These things retain their value too much for me to afford another one. I will probably end up with a subaru since I want good in the snow, but would like better fuel economy than the 4runner for my 80mi commute.

 

[02SE]

It sounds like the flywheel might be broken. Which is not unheard of.

 

[hearno]

timing belt slipped/broke?

 

[RPTFE00]

Agreed ^ check under the timing cover and see if your belt is still in tact. While revving after it happened did you hear some bad noises like a clunking or a rhythmic ticking?

 

[Nelsonmd]

The timing belt is ok, I just took the cover off and everything underneath looks fine.

It sounds like the flywheel might be broken. Which is not unheard of.

This is what I'm thinking. The starter gear engages the flywheel right? When I turn it over, it sounds like i am just spinning the starter motor. I am guessing it's either broken flywheel gear or broken starter gear.

The question I still have though is whether a broken flywheel would cause me to lose drive when I was already driving? I didn't think that the gears on the flywheel carried the primary drive force.

Thanks for the quick replies guys.

 

[RPTFE00]

Possibly no compression? You said you heard a solid clunking? But the engine was still running.

 

[02SE]

This is what I'm thinking. The starter gear engages the flywheel right? When I turn it over, it sounds like i am just spinning the starter motor. I am guessing it's either broken flywheel gear or broken starter gear.

The question I still have though is whether a broken flywheel would cause me to lose drive when I was already driving? I didn't think that the gears on the flywheel carried the primary drive force.

Thanks for the quick replies guys.

Starter engages the ring gear on the flywheel.

Flywheel is bolted to the crankshaft.

Torque Converter is bolted to the flywheel.

A broken flywheel would explain everything you've described.

 

[Nelsonmd]

So that explains the non starting, but would it cause the crankshaft to just spin while I was already driving? If its just flywheel ring teeth broken, then I don't think I would have lost drive while driving.

Is the transmission drive plate a separate component from the flywheel, or are they the same component? The manual shows it in a box like it is the variant for the A/T. Does the power from the crankshaft go through the drive plate teeth?



I suppose to fix either of these this means dropping the transmission?

How much work am I really looking at here? If it's just the 1 part, then I'd hate to scrap it and take the loss (or donate it rather) because of just the one part, but I don't know how I could really sell it with this kind of problem and get any more than the scrap price.

On the other hand, I think it's probably not going to be cost effective to have this done at a shop, and unless y'all tell me it's really easy, I'm not sure I have the time/motivation for such a major job.

Thanks again for the quick replies guys, this is the fastest (likely) solution I have ever seen on here...

 

[BrianSD_42]

Don't leave bro. You're one of the few automotive engineers (still in school right?) on this site.

This site needs more Master Techs and Engineers not less.

 

[legokcen]

Is the transmission drive plate a separate component from the flywheel, or are they the same component? The manual shows it in a box like it is the variant for the A/T. Does the power from the crankshaft go through the drive plate teeth?

I suppose to fix either of these this means dropping the transmission?

How much work am I really looking at here?

On the other hand, I think it's probably not going to be cost effective to have this done at a shop, and unless y'all tell me it's really easy, I'm not sure I have the time/motivation for such a major job.

Thanks again for the quick replies guys, this is the fastest (likely) solution I have ever seen on here...

They're pretty much bolt on. I don't know if removing the flywheel takes any special tools. I've done it before, but not on a 4Runner. Removing the transmission isn't hard if you can get under the truck. Unbolt the drive shaft and remove. Use a jack to take the weight if the transmission as you unbolt from motor and truck chassis.

 

[02SE]

but would it cause the crankshaft to just spin while I was already driving?

Yes, it would.


The Flywheel for an automatic transmission equipped vehicle, is also called a flexplate. They are relatively thin stamped steel.

It's not the ring gear itself that typically breaks. Instead, the thin stamped steel usually breaks outside of of the bolts that hold it to the crankshaft, but inside where the Torque Converter bolts to it.

Here's a picture of a typical Flexplate failure.


That piece with the holes that used to be in the middle of the Flexplate, is what is bolted to the crankshaft.

The Torque Converter would bolt to the flexplate through the holes evenly spaced around the flexplate.

 

[Nelsonmd]

Don't leave bro. You're one of the few automotive engineers (still in school right?) on this site.

This site needs more Master Techs and Engineers not less.

Haha, no I graduated 10 years ago, been in industry ever since. I certainly don't want to leave, this has been a great forum, but I do have to make the right decision for my situation. If I don't get a 4runner, I'll have alot of random parts to sell here...

The page I was looking at was this one, it shows the flywheel and a drive plate, not sure what the inset box means. By my reckoning, the flywheel teeth breaking wouldn't cause me to lose drive power while driving and a freely reving engine when it was still on. I thought maybe the drive plate might take on the full driving power on it's teeth, but I'm just not super strong on the transmission configuration.

I did look on CL and searchtempest, and there are definitely some options for me, but the biggest requirement for me this time around will be no rust, so I may need to go down south for it. I'll have to decide if I still want a truck, or want something with better fuel economy for my commute.

 

[Nelsonmd]

Yes, it would.


The Flywheel for an automatic transmission equipped vehicle, is also called a flexplate. They are relatively thin stamped steel.

It's not the ring gear itself that typically breaks. Instead, the thin stamped steel usually breaks outside of of the bolts that hold it to the crankshaft, but inside where the Torque Converter bolts to it.

Here's a picture of a typical Flexplate failure.


That piece with the holes that used to be in the middle of the Flexplate, is what is bolted to the crankshaft.

The Torque Converter would bolt to the flexplate through the holes evenly spaced around the flexplate.

Ah, I see. That makes sense now... Thanks for the picture, now I picture it easily. That sounds very possible...

 

[Brique]

If you find anything in Nashville you want eyes on, I'll be happy to give a first look for you.

 

[LittleCaesar]

I can't believe you have an 80 mile commute. I know you have the bike but still. A Subie makes more $$$ sense, though be very thorough when checking out a used one.

Flexplate most definitely.

I hope the girlfriend got home OK.

 

[TheDurk]

Matt, I just want to say that if you leave, you will be missed. You had a lot of great input, and I considered you our resident 'rust guru' --a title I'm sure you would prefer to have avoided.

I wish I could help, but I'm strictly a stick shift mechanic. Happy to say, these have a REAL flywheel, about two inches of solid steel and the ring gear has a lot of beef. I hate the look of that flexplate thingy. Glad I don't have one.

For what it's worth, the solid part of the flywheel bolts up to the crank and is real easy to remove on a 5-speed. I would think the A/T's would attach the same way. If that's the only damage, replacing it should be no more difficult than replacing a clutch. I did mine my self, on jackstands, two years ago. Not easy, but doable.

 

[Nelsonmd]

Thanks for the kind words guys. Everything you've said is why I have stuck around here so long, so many guys here eager to help and in general be respectful.

I am thinking more about going for the fix since y'all have made it sound relatively straightforward. The flywheel shows as about $200 new, and I'll need to get a transmission jack. Do you guys think that a motorcycle/ATV lift would work just the same for the transmission? It's cheaper at HF, and I could use it for my motorcycles afterwards.

I guess I should start putting together a parts list... Let me know what else I should be replacing:

1. Flywheel - 32101-35010
2. Transmission dip stick - 35013-34060 (I accidentally cut this when removing my old CAT, it recently broke completely and I have been trying to find a replacement, but none in the salvage yards right now...)

What else should I get? I am parked on the street right now, so I may have to do this in a single weekend, so I'd like to have everything I'll need on hand ahead of time.

 

[SilverRidgeRunner1]

Rear main seal wouldn't be a bad idea and the transmission pump seal would be recommended thing since you're in there.... The jobs is just simply long but not bad at all. If you have access to a lift its a breeze but on the ground it's just time consuming.

 

[Nelsonmd]

Well, the shop next door just estimated that it'd be about $1k to drop the transmission and replace the flywheel. This is quite a bit cheaper than I expected, so I might take it over to him on Monday and have him do it for me.

I've been car shopping, but nothing is tickling my fancy. The 4runner meets all of my wants/needs except for fuel economy and traction control. To get everything I want in another car would put me either in a newer truck, which isn't cheap to buy and still sucks for economy, or upwards of 18k for a more modern subie, which still doesn't have amazing fuel economy. Nothing has been standing out except a subaru forester or outback, and I'm not sure I'm ready to go that granola...

 

[JayRolla]

Well, the shop next door just estimated that it'd be about $1k to drop the transmission and replace the flywheel. This is quite a bit cheaper than I expected, so I might take it over to him on Monday and have him do it for me.

I've been car shopping, but nothing is tickling my fancy. The 4runner meets all of my wants/needs except for fuel economy and traction control. To get everything I want in another car would put me either in a newer truck, which isn't cheap to buy and still sucks for economy, or upwards of 18k for a more modern subie, which still doesn't have amazing fuel economy. Nothing has been standing out except a subaru forester or outback, and I'm not sure I'm ready to go that granola...

Yeah, dont go granola!!!

Make sure they use an OEM flywheel.