I bought a 93 ZJ about 4 months ago and love the thing, however... This morning on my way to work I stopped at a red light, and when I started to accelerate (got to about 10mph) BANG! It was like the drive shaft blew out or something to that effect.
Here's the thing though. I kept driving. I traveled another 28 miles hit 4 more red lights 55 to zero and back again and Nothing??? No clunks, rattles, pulling to one side or the other. Seemed to drive normal. Any ideas what it was that almost made me shat myselfs? TIA

 

When you heard the bang and got out to investigate, was there any slop in the u joints. Massive this weekend open your diff. Check tranny fluid. Noggin pokin time

 

I should add I've looked at all the suspension parts and everything visible under neath is tight.

 

That's good to know you started investigating. Hearing a bang, to me, three things come to mind. Transfer case going from 4hi to 2wd on dry.pavement, happened to me once one winter it didn't want to shift on the fly out, second thing would be the tranny slipping or third is something with the rear end. Other people with chime in. Luke I said, check fluids, you can open rear diff and if its been a while since you've opened it, some fresh fluid wouldn't hurt. Also check play in your pinions. Etc etc etc. Do some noggin pokin and tell us what you find.

Next time you hear a bang though, its a good idea to pull over if possible and check everytime one time fast so you don't damage your whole jeep possibly even more. A busted DS can rip your TC up or rear end.

 

U joints and everything else seems fine. I just checked the rear axle fluid and its pretty nasty... (Previous owner said "just changed it" haha serves me right for believing) so is it possible it just bound up and I got away with one after changing the rear gear fluid? The bang was pretty loud.

 

Did you open the cover. Everything looked good. Also question, do you have drum brakes or disc, forgot if your year which it was. If drums, open the drums and make sure nothing got loose. I have seen that happen once to someone. They did a rear disc conversion. They didn't know one of the old lugs was stuck inside the backing plate. They drove around, it bound up in there and caused a loud bang and slight hesitation. Then drove fine like nothing happened. Exactly how you explained it.

 

It's a 93 with the stock drum brakes, don't think they would be the issue due to the fact it took off normal with no drag or clunks from initial start. I was over half way through the intersection before it happened.
And I'm "working" right now so I only pulled the plug to check the fluid.
Untili can pull the cover about 4 pm I understand anything is speculation but could it have been an axle shaft busting? I'd imagine it would still drive right. Also I havnt played with the 4x4 since I tested it 4 months ago.

 

When you get some time. Give her a good once over. As for a busted axle shaft, not fully sure how that feel, never had that issue personally. Hoping it was nothing major. Just know you'll be doing some jeep time this weekend and showing her some love

 

if an axle shaft broke it would have walked its way out of the axle housing. I would check your trans mounts and motor mounts too wile you are looking around. Is your jeep lifted. get us more info on the jeep it will help with understanding of were it may be coming from. Since it is a ZJ do have the NV249 AWD transfer case? if it is, your viscous coupling could be on its way out.

 

No lift or any other cool accessories yet jus a stock 23 year old Laredo. 278k on the body but engine and trans were both ordered from factory 2 years ago (according to paper records) the vin on the block matches reciept so I believe that to be true. As for the transfer case its the NV242 with 5 operating modes. (Is that a good one? Lol) Is it possible for a component of that to give me trouble even though I havnt used 4X4? I've never owned one before this so its new for me.
As far as motor or trans mounts that was actually my first thought since it continued to go and it was impossible for me to pin point the location of the bang. Looking at them though everything looks solid. I've alternated driving forward and reversing a few times with no issue.

 

I have the rear end lifted and with both tires off the ground I rotate one and the other rotates opposite. Good thing :-) should there be any play when stopping and rotating it the other way though? It seems as though its pretty sloppy.

 

What axle do you have?

 

Only if it's a c-clip axle.

 

Imhonestly not sure and the plate thats stamped has rusted beyond reading. Does the cover help you identify it? I just drained the fluid since its a good idea either way and see nothing obviously out of place inside. However while rotating the driver rear tire again the passenger rear drum did start making a rattling noise so im going there next. As soon as it stops pouring rain that is.

 

After doing a little research I've come to believe its the d35