Flexplate Bolts?

Long story short;

-Transfer case exploded driving down the highway. Towed jeep home.
-Installed another T-case. Jeep still doesn't move.
-Motor starts up fine. When i put the jeep into gear you hear a noise in the bellhousing area.

The video attached is the noise the jeep makes when in gear.

I think that when the T-case locked up or whatever happened (The t-case bounced down the highway then the jeep stalled) the torque transferred back through the rest of the components and the flexplate bolts snapped. I don't know how to check if anything else is damaged. I'm questioning whether the AW4 is cooked or not.

Anyways i have questions;

1. I've never pulled a tranny on a jeep. Is it simple? T-case off, then unbolt the tranny? Anything else involved? Is it heavy?

2. How do i tell if the tranny is cooked?

3. How do i tell if the torque convertor is cooked?

4. Is there anyway to figure out why my jeep isn't moving before i rip the entire thing apart? It's my Christmas break job.

99 XJ/4.0/AW4/NP231

All help is appreciated.

http://www.youtube.com/watch?v=7gTHevjIMVs

You can take off an oil cooler line and see if oil still pumps through the transmission.

I highly doubt that the flex plate to torque convertor bolts snapped off. Remember that the torque convertor is a fluid coupling and has a lot give. Easy way to find out is to pull the dust shield off and look. With the amount of destruction there, I wouldn't be surprised if something in the tranny let go, maybe a snapped shaft or something. Or something having to do with the sprag (overrunning clutch or bearing).

On a side note, looking at that pile of parts, what the heck happened? It almost looks like you have big tires and something drastic happened in the trans and it locked up, and the forward momentum twisted the transfer case off of the back of the tranny. Am I close?

Edit- I just looked up your original thread on this "Transmission/T-case Problem?". Wow. Hard to believe that a bad double cardan could do that. I could be wrong but it still seems more likely that the tranny had some sort of catastrophic failure. I've seen driveshaft failures many times and since they are thin wall tubing, that usually is the sacrificial part.

That just doesn't sound likely to you? I mean that noise sounds like it's coming straight from the bellhousing. I've never taken one of these apart, and quite honestly i have no idea what's in there or how it could break. I just know that doesn't sound quite right in there.

I know this question sounds dumb, and probably is, but where is this dust shield i can pull off? Will this let me look straight into the bellhousing or what?

I have no idea how an automatic transmission works besides the fact that it's super complicated. Is there any way to tell if mine is toasted or should i just find another known good AW4 and swap that in? Should i buy a new torque convertor and flexplate while i'm in there or is that unrealistic? I personally don't know.

That sounds about right. Honestly i don't know the sole cause of the T-case ripping out of the jeep. The only thing i know is that it did indeed rip out of the jeep and it was rather violent when it came out.

I think the double cardian locked in an upright position (like a 90) you can see the mark on the driveshaft in my other thread and instead of the force getting transferred through the thin wall tubing of the actual driveshaft it all went into those two double cardian pieces that were locked together and that had enough force to twist the T-case out. It was rather quick. It went from a slightly bad vibration, to a really bad vibration, to a wholly mother of god something is about go wrong whole jeep vibration and then BAM!

I'm just speculating though. I don't know. I just know that i want to get this jeep back on the road. Hahaha.

I may sound like a vulture, but hang on to that differential. If it's not ate up its worth a couple bucks. Good ones are hard to come by.

The dust cover is the sheetmetal cover on the bottom front of the bellhousing that can be seen if you crawl under theback of the engine.

There's two large bolts and several smaller bolts holding it on. Remove these bolts and you can remove the dust cover. If your exhaust system is stock you probably won't be able to remove the left large bolt. The dust cover is slotted to clear this bolt.

Rotate the crankshaft by the vibration damper bolt in a clockwise direction and each of the four torque converter to flex plate bolts will come into view. If any bolt is missing, look in the bellhousing for it. If the head has been shearded off the trans will have to be pulled to get the sheared bolt out of the torque converter. If the bolts are just loose, tighten them (27 ft./lbs.) and check the bolt holes in the flex plate for elongation and cranks anywhere onthe flexplate.

If all of the bolts are there and secure you can do a quick check to see if the torque converter and the trans oil pump work.
Leave the engine sit over night so the trans fluid is at ambient temp. Pull the trans dipstick and check to see where the fluid level is; it should be near the top of the dipstick full range. With the trans in Park, start the engine and immediately pull the trans dipstick, the fluid level should have dropped to near the bottom of the dipstick. If it didn't, either the torque converter or the engine oil pump is bad.

Edit: Edit text is in Blue.

Sidewinder, i forgot to mention. I know you said the torque convertor has a lot of give, but i failed to mention that this happened at around 65-75MPH. I'm not 100% positive, but i'm pretty damn sure that the torque convertor was locked when the T-case came out of the jeep because i was cruising down the highway.

I'll keep that diff but i don't plan on doing anything with it.

Is the vibration damper bolt under the dust cover? I've never heard of that bolt before, and haven't a clue where it is.

Thanks for the clear as day instructions. They seem easy enough to follow. I will report back once i get a minute to work on the jeep. Can't get anything done for a few days at minimum though.

Oh, and another thing i noticed. Before i installed the transfer-case onto the jeep i could shift the gears (2hi, 4hi, n, 4lo) without problem. Just by using a wrench on the shifter on the case. Now that it's installed on the jeep i can't even shift it anymore. Not sure why.

The T-case bolted up fine but i'm wondering if something within the case is bad. If i pull the case off and the tranny output shaft is spinning does this mean that the only problem is within the tcase?

Kingkong0192 said:

Sidewinder, i forgot to mention. I know you said the torque convertor has a lot of give, but i failed to mention that this happened at around 65-75MPH. I'm not 100% positive, but i'm pretty damn sure that the torque convertor was locked when the T-case came out of the jeep because i was cruising down the highway.

I'll keep that diff but i don't plan on doing anything with it.

Is the vibration damper bolt under the dust cover? I've never heard of that bolt before, and haven't a clue where it is.

Thanks for the clear as day instructions. They seem easy enough to follow. I will report back once i get a minute to work on the jeep. Can't get anything done for a few days at minimum though.

Oh, and another thing i noticed. Before i installed the transfer-case onto the jeep i could shift the gears (2hi, 4hi, n, 4lo) without problem. Just by using a wrench on the shifter on the case. Now that it's installed on the jeep i can't even shift it anymore. Not sure why.

The T-case bolted up fine but i'm wondering if something within the case is bad. If i pull the case off and the tranny output shaft is spinning does this mean that the only problem is within the tcase?

Click to expand...

The vibration damper is in the front of the engine. It's the bottom pulley that the drive belt goes around. The bolt holds the damper on the end of the crankshaft. 3/4" hex on the bolt.

Shift the transmission into neutral and try shifting the TC. If it won't shift into neutral the trans is probably shot.

When you get the dust cover off and if you find all the flex plate bolts sheared off, you'll need a new flex plate, flex plate to crankshaft bolts, flex plate to torque converter bolts, torque converter, and possibly a transmission.

Oh oh. I thought it was a totally different bolt. I've only heard that bolt referred to as the crankshaft bolt.

I'll try shifting the tranny into neutral and then shifting the t-case to see if that helps. However, i did put the thing into neutral to push it out of my garage and down the driveway onto the lawn. I'm pretty sure the only thing holding it in place at this point is the parking paw.

EDIT; Just went back outside to attempt to move the jeep. I went to start it and nothing happened. All the gauge lights came on, and the jeep didn't crank at all. Tried a few more times, nothing. Put it into neutral to see if i could move the jeep and then i went to start it and it fired right up. I figured NSS, but i tried to repeat this procedure and it won't start up in neutral or park now.

Something is holding the jeep in place even when in neutral. I can't even push the thing. Won't budge at all. And no, there aren't any rocks under the tires. Haha. It's even parked on a slight hill.

Could this be an electrical issue? Or would neutral still allow it to roll? I did lose a bunch of wires like the 02 sensors, all the t-case wires, etc when the t-case went bouncing down the highway. It is throwing 2 codes. (2 for the 02 sensors.) Nothing about the tranny.

Would you buy all of these parts secondhand? (i know i'm going to get a secondhand AW4) but i've never had to buy a torque convertor, flex plate, etc, and i'm not sure how much they go for.