Vehicle: 73 88 NAS Series III
Problem: Knocking sound coming from the main gearbox.
Trouble shooting actions to date: At first I thought it was a clutch issue. Clutch inspected and driven plate changed. Also replaced the rear seal. Why not?! Everything was removed! Inspected the engine, arms etc. when sump was removed. Everything appeared in order except for metal in the sump! No metal when transmission/ transfer case oil was drained. Everything cleaned, fluids changed and buttoned up and the knocking sound still present.
Diagnosis: Drive in the main gearbox had slight side to side movement (checked it when transmission was out while I was changing clutch plate). A bearing is shot somewhere in the transmission. My guess is in the front output shaft.
Video: When I was shooting the video I put my hand over the area of the front output/bell housing/main gearbox and it muffled the knocking sound. This leads me to believe that the problem is in the main gearbox.
View My Video
I plan to remove the trans and open it up. I figure I will run into a broken bearing or the like. This is the first time I've open up a transmission and am going into it blind.
I've read other posts on the forum that were helpful (Oh noooo...transmission and the rebuilt link in that post). The OP said that his rebuild cost 1k! I'd like to replace a bearing or two and drive on.
Should I consider a new transmission?
I also need to ID my transmission (I read people talking about an "A" or "D").
Any comments/suggestions on a fix. Any and all comments are appreciated! Thanks!
Problem: Knocking sound coming from the main gearbox.
Trouble shooting actions to date: At first I thought it was a clutch issue. Clutch inspected and driven plate changed. Also replaced the rear seal. Why not?! Everything was removed! Inspected the engine, arms etc. when sump was removed. Everything appeared in order except for metal in the sump! No metal when transmission/ transfer case oil was drained. Everything cleaned, fluids changed and buttoned up and the knocking sound still present.
Diagnosis: Drive in the main gearbox had slight side to side movement (checked it when transmission was out while I was changing clutch plate). A bearing is shot somewhere in the transmission. My guess is in the front output shaft.
Video: When I was shooting the video I put my hand over the area of the front output/bell housing/main gearbox and it muffled the knocking sound. This leads me to believe that the problem is in the main gearbox.
View My Video
I plan to remove the trans and open it up. I figure I will run into a broken bearing or the like. This is the first time I've open up a transmission and am going into it blind.
I've read other posts on the forum that were helpful (Oh noooo...transmission and the rebuilt link in that post). The OP said that his rebuild cost 1k! I'd like to replace a bearing or two and drive on.
Should I consider a new transmission?
I also need to ID my transmission (I read people talking about an "A" or "D").
Any comments/suggestions on a fix. Any and all comments are appreciated! Thanks!
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