Transmission loud knocking noise?

[AutoVation]

Driving back from Shindig, I dropped the transmission from OD to 3 and accelerated (not too aggressively). I heard a loud metal on metal knocking noise, almost like someone was banging on the floorboard with a large wrench. The bang was 1-2x per second and seemed to relate to the speed of the truck. I put it back into OD and the noise disappeared. WTF was that noise?

 

[wheels]

Re: Transmission loud knocking noise?

Transmission lever moved when you shifted into 3 and was making contact with the propshaft?

 

[REVEREND HARMON]

Re: Transmission loud knocking noise?

Could be alot of things....how are your motor mounts? the trans is real close to the firewall lip and could have been hitting it. Tc chatter maybe?....Or your prop shaft could be going out. Fuel lines attached to the tranny still?They could be flopping around on top of it. Trans mount still good?

Also check the torsion mounts. Ive seen where one was torn and under heavy load it was tapping the frame pretty good.

 

[AutoVation]

Re: Transmission loud knocking noise?

I've got the upgraded GB propshaft. Tranny fluid is nice and bright. I'll get in there and check the mounts. If it was a mount or something like that, wouldn't it do it when in OD also?

 

[wheels]

Re: Transmission loud knocking noise?

I've got the upgraded GB propshaft. Tranny fluid is nice and bright. I'll get in there and check the mounts. If it was a mount or something like that, wouldn't it do it when in OD also?

Did you modify the shift lever? The upgraded propshafts are bigger and need more clearance from the shift linkage. Check the propshaft and see if there are marks in it from anything rubbing on it while its spinning.

 

[AutoVation]

Re: Transmission loud knocking noise?

Did you modify the shift lever? The upgraded propshafts are bigger and need more clearance from the shift linkage. Check the propshaft and see if there are marks in it from anything rubbing on it while its spinning.

I think this is probably the issue. The shift lever was not modified.

 

[sytyguy]

Re: Transmission loud knocking noise?

Whew....I thought the Shindig ate another trans for a minute.

 

[cloneman315]

Re: Transmission loud knocking noise?

Could always blame it on earl...