Hello,, quick back story, 1978 Fj40 JimC 2f, 4 speed, stock t case, 4 inch springs, super skinny swampers and lock-rite in the rear.. It's torque-y, twitchy, and sticky.
2f was rebuilt with a new clutch and the T case was rebuilt.. These only have a thousand miles on them.. Then I tore it down due to rotted frame. Few wheeling trips, but mostly parked.
I'm just now getting it back on the road after a doing the frame swap and full cage install.. So it was completely disassembled and reassembled.. I did leave 2f/trans/tcase together during frame swap.. But it's mostly been sitting during this last 3 year period..
As I said earlier, It has a lock-rite locker in the rear, and super skinny swampers.. So it's kinda sticky on pavement.
Soooo,, When I release clutch to take off (whether 1st or reverse), there is quite an audible single pop/clunk. As if something is binding and then releasing. It shifts fine once rolling. And rolls down the road great. But it has a single thud when I release the clutch from a stop. If I release the clutch extremely slow with no torque there is no thud..
The clutch does seem to release higher up the pedal than I remember.. But I removed clutch inspection cover and it seems to be doing what it should be doing upon initial inspection (not running with wife pushing in clutch).
I've went around and re-torqued and greased everything I could think of (just to double check my initial work). I tightened all the suspension bolts, u bolts, engine/trans mount bolts, drive shafts bolts, shackle bolts, etc.. Still pops/clunk when I release clutch to go.
Before this rebuild. I didn't have the clunk.
My driveshafts appear to be in phase, they are old, but no real slop in them that I can tell.
Will and old drive shaft cause a that loud of a thud/bang that you can feel/hear if you can't detect any slop in them?
It sounds as though something is perhaps binding then clunking and then releasing.. You can definitely feel it too..Especially if I kinda pop the clutch a little more than normal (not revving engine, just a faster clutch release than normal).
When I'm driving, if I hit 2nd or 3rd under fast acceleration, i can sometimes get a little clunk (but only if I'm really ON the throttle, power shifting and NOT all the time), but not loud like initial take off. And no sounds under normal acceleration.
I know it's hard to diagnose via this post... But I've searched and searched and searched and can't seem to find anything regarding the thud I'm referring to..
I'm really itching to start driving this thing again because my sons are old enough to enjoy it with me now.., but I don't want to destroy something else during shakedown. Especially if it's the beginning of a detrimental failure...
Any quick suggestions of ways to find the culprit? im worried it's could be a bad output shaft bearing or shaft? How do I check this?
I removed rear driveshaft, put in 4hi, locked front hubs, still clunks!
Does this sound like possible loose output shaft issues ? Ujoint issues? Locker issues? Clutch adjustment? Or 4inch springs and un-shimmed rear end pinion angle issues? Drum brakes sticking?
I've greased the driveshafts, checked the e brake bolt 90lbs. I did noticed there is about 1/32 of play if I REALLY REALLY YANK/PUSH up on the e brake bell via driveshaft... But it doesn't feel excessive by any means.. But maybe this is enough?.. Is this a sign of a loose output shaft bearing? Bad bearing? Bad shaft (splines looked good inside e brake service e Brahe during rebuild). Haven't inspected the rear Dif yet,, but Zero slop at pinion..
I can't pinpoint where it's coming from.. And it's driving me nuts.. If I just release clutch slow, it would never happen.. But I know there is an issue lurking..
Thanks in advance.
Kevin
2f was rebuilt with a new clutch and the T case was rebuilt.. These only have a thousand miles on them.. Then I tore it down due to rotted frame. Few wheeling trips, but mostly parked.
I'm just now getting it back on the road after a doing the frame swap and full cage install.. So it was completely disassembled and reassembled.. I did leave 2f/trans/tcase together during frame swap.. But it's mostly been sitting during this last 3 year period..
As I said earlier, It has a lock-rite locker in the rear, and super skinny swampers.. So it's kinda sticky on pavement.
Soooo,, When I release clutch to take off (whether 1st or reverse), there is quite an audible single pop/clunk. As if something is binding and then releasing. It shifts fine once rolling. And rolls down the road great. But it has a single thud when I release the clutch from a stop. If I release the clutch extremely slow with no torque there is no thud..
The clutch does seem to release higher up the pedal than I remember.. But I removed clutch inspection cover and it seems to be doing what it should be doing upon initial inspection (not running with wife pushing in clutch).
I've went around and re-torqued and greased everything I could think of (just to double check my initial work). I tightened all the suspension bolts, u bolts, engine/trans mount bolts, drive shafts bolts, shackle bolts, etc.. Still pops/clunk when I release clutch to go.
Before this rebuild. I didn't have the clunk.
My driveshafts appear to be in phase, they are old, but no real slop in them that I can tell.
Will and old drive shaft cause a that loud of a thud/bang that you can feel/hear if you can't detect any slop in them?
It sounds as though something is perhaps binding then clunking and then releasing.. You can definitely feel it too..Especially if I kinda pop the clutch a little more than normal (not revving engine, just a faster clutch release than normal).
When I'm driving, if I hit 2nd or 3rd under fast acceleration, i can sometimes get a little clunk (but only if I'm really ON the throttle, power shifting and NOT all the time), but not loud like initial take off. And no sounds under normal acceleration.
I know it's hard to diagnose via this post... But I've searched and searched and searched and can't seem to find anything regarding the thud I'm referring to..
I'm really itching to start driving this thing again because my sons are old enough to enjoy it with me now.., but I don't want to destroy something else during shakedown. Especially if it's the beginning of a detrimental failure...
Any quick suggestions of ways to find the culprit? im worried it's could be a bad output shaft bearing or shaft? How do I check this?
I removed rear driveshaft, put in 4hi, locked front hubs, still clunks!
Does this sound like possible loose output shaft issues ? Ujoint issues? Locker issues? Clutch adjustment? Or 4inch springs and un-shimmed rear end pinion angle issues? Drum brakes sticking?
I've greased the driveshafts, checked the e brake bolt 90lbs. I did noticed there is about 1/32 of play if I REALLY REALLY YANK/PUSH up on the e brake bell via driveshaft... But it doesn't feel excessive by any means.. But maybe this is enough?.. Is this a sign of a loose output shaft bearing? Bad bearing? Bad shaft (splines looked good inside e brake service e Brahe during rebuild). Haven't inspected the rear Dif yet,, but Zero slop at pinion..
I can't pinpoint where it's coming from.. And it's driving me nuts.. If I just release clutch slow, it would never happen.. But I know there is an issue lurking..
Thanks in advance.
Kevin
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