The 1947 - Present Chevrolet & GMC Truck Message Board Network - View Single Post - T-400 speedo gear shaft too big

Judgeyoung · 05-11-2017, 03:42 PM

What I "may" have learned is that the natural color drive gear can also be a 15 tooth, meaning that I need a 34 tooth driven gear. I got one of those today, and, miraculously, it is the correct diameter. Apparently, in order to make it harder to put the "larger number of teeth" gears into the "smaller number of teeth" housings, they made the shafts different sizes. It looks like I at least have the correct gear.

I also think that the bearing stub from the old gear may have sheared off in the boss inside the tailshaft, and while likely difficult because of not being able to see, I think that I can use a left hand bit, or other device, and carefully remove the stub from the housing. If not, I will have to remove the housing, which might be a good idea anyway since I still have not felt or retrieved the remainder of the old gear...

I know that trying to answer my own question is pretty lame, but maybe someone else with a similar issue will run across this and it might be of help.

Of course, I am certainly open to one of you experts putting me on the correct track!

05-11-2017, 03:42 PM	#2
Judgeyoung Registered User Join Date: Apr 2017 Location: Abilene, TX Posts: 6	Re: T-400 speedo gear shaft too big What I "may" have learned is that the natural color drive gear can also be a 15 tooth, meaning that I need a 34 tooth driven gear. I got one of those today, and, miraculously, it is the correct diameter. Apparently, in order to make it harder to put the "larger number of teeth" gears into the "smaller number of teeth" housings, they made the shafts different sizes. It looks like I at least have the correct gear. I also think that the bearing stub from the old gear may have sheared off in the boss inside the tailshaft, and while likely difficult because of not being able to see, I think that I can use a left hand bit, or other device, and carefully remove the stub from the housing. If not, I will have to remove the housing, which might be a good idea anyway since I still have not felt or retrieved the remainder of the old gear... I know that trying to answer my own question is pretty lame, but maybe someone else with a similar issue will run across this and it might be of help. Of course, I am certainly open to one of you experts putting me on the correct track!