Last night I was out heading home from a bar-b-q and I decided to do a small burn out The truck was stopped and I did a mild 3rd gear boost launch at about 10-12psi when the truck left I heard a clunk!! and the tires spun for a little ways maybe 15-20ft before I got out of it, from that point on I could not get it into any gear so I limped it over to the side to see what I broke, of course nothing I could see with the naked eye. I had my wife push on the clutch while I checked to see if the slave cylinder was working back and forth and everything was operating correctly from what I could tell with a flashlight there is no hydraulic fluid anywhere but when the truck is running there is no way you can get it into gear, when the truck is stopped you can. So it is staying engaged the whole time. Any thoughts I'm thinking it is something with the hydraulics of the truck and since I never upgraded the system when I put the DD in I'm thinking the stock hydraulics went belly up on me. I't sure as heck can't be the clutch right?

 

You know the more I think about it how can the hydraulics be the problem if there is fluid and the slave cylinder is working?

 

A loud clunk doesn't sound like the hydraulics to me. More like input shaft, or $$ tranny repair...

 

Well I thought these 1"3/8 imput shafts were strong and could hold up to at least one boost launch aside from taking the tranny down is there any way that I can confirm this or something else?? Boy I sure don't want to go and do this all over again

 

Maybe the fork on the throwout bearing broke?? You can float your gears once you get moving right? You would think it would just tear up the clutch surface doing a 3rd gear launch not the hyd. side of it, Does it make any noise at all when you press the clutch in?

 

Input shaft gone should make it easy to go into gear with truck on or off. The input shaft is what makes it hard to shift while the truck is on vs truck is off... so that should be fine.

If your able to get it into gear while off but not while running.. sounds like something "clutch wise" is amiss.

Just for fun, what happens when (truck off) you put it in gear, push in the clutch, and try to start the truck?

What we are looking for is if pushing in the clutch is really disengaging the transmission.

You may have also destroyed some synchros (if the trucks even have them.. lol). Synchros commonly go during hard launches. Ive threw some out of the tranny case before on previous vehicles.

If you can put it in say 2nd gear, push in clutch, start truck, and it doesn't do anywhere.. then you can pretty much safely guess the problem is all inside the tranny. From there, see what happens when you go to shift while driving.. if you can pull it out of gear ok and maybe try not to use the clutch and just RPM match to squeeze it into the next gear.

A few things to try to give us all a little more info on where the problem lays.

 

If you broke a shaft it should have been dead in the water, you said it spun for 15-20 more feet so the shaft sounds good to me.

 

Are the DD capable of doing a 3rd gear launch or not because thats what there designed to be able to handle in limited amounts right?

 

Alright I think the problem is fixed....I got a ride back over to the truck this afternoon started it up and tried to put it into gear....nothing no go. So instead of towing it we decided to try rpm shifting it so we started it in 3rd gear the truck kept lurching forward and not starting then all of a sudden the truck starts and I'm now able to drive the truck with no problems everything is shifting like it should and working just fine. Only thing we can think of is the tranny got locked up between gears and buy trying to start it in 3rd gear popped it all loose . Strange has anyone else had this happen? As for now the truck is running like it was before hand, go figure who the heck knows I sure appreciate all the info you guys gave out and hopefully once again my experience helps out for someone else in the future. Thanks everyone and thanks DTR for the ability to do this for free.

 

So, . . . . . Have you thanked your Lucky-Stars yet?

 

3rd gear, shoot mine used to do 4th gear burn outs all the time. BTW how old is the clutch, I know some of the first ones had a problem that has long since been fixed

 

Lucky you.. id be very worried of that transmission now.

I havent seen the inside of these ones, maybe a tranny tech can chime in, but transmissions can still operate without synchos or certain spider gears so its possible a synchro or some small spider gear snapped and got stuck and has since been dislodged.

May be 100% different for these trucks, but be on the the lookout!


Does it shift the same exact way into every gear? (same resistance?)

 

Sounds like the clutch just got a little warm, I've almost hit parked cars when the FE Hung up a few times! Hopefully Peter will chime in here! I'm sure theres a technical answer, (better yet a reason we shouldnt do it ) but im not sure of what it is

 

The clutch is about 2 months old with approx 1500mi on it it seems to shift with the same resistance in every gear hopefully it is just a fluke. I would really like a tranny guy to chime in or better yet the man himself Peter!!! O and by the way I have been thanking the good Lord up above

 

What would cause an FE to hang up?