NP-435 speed gear help.

[claremore125]

I have an 86 f250. It has the 300 straight 6 with the NP435 granny four speed in it. I have owned the truck for about 12 years now and it has sat about the last 8 years. This is my new project. The speedometer has never worked as long as I've owned the truck. I know its the gear in tail section of the trans because when pull the cable out of the trans and spin the gear the speedometer works. My question is how hard it it to replace that gear In the trans, is it expensive, and is it even worth jacking with it. I have a very extensive mechanic background but I'm not a transmission guy. Thanks in advance for all you help. Comments and suggestions are always welcome.

[BobbyFord]

It's very easy. Pull the driveshaft yoke and extension housing off and it will be self-explanatory. Just keep forward pressure on the output shaft when you pull the housing off (because I can't remember if the rear shaft will try to come out when you remove the housing).

[fireguywtc]

No, the shaft will not try and slide out on the NP 435. When I swapped parts on my tansmissions I recall the shafts staying in place the entire time when the rear housing and everything was off.