K30 gear question.

[77_Jimmy]

I recently bought a K30 for parts , but I going to build it and leave my Jimmy in the garage. Anyway I cannot find any markings on the axles or any tags on the truck. It has 350 sm465 np205 d60/14b drivetrain. Any clues what the gear ratio is. First build up is gonna be cheap so I'll let the gears dictate tire size. Thanks. Oh yea it's a 1980.

 

[Avery4jc]

Since it's a newly acquired truck it might be worth while to pull the rear diff cover and kill two birds with one stone. You can inspect the gears and at the same time count the teeth on the ring/pinion and be 100% sure what gearing you have.

 

[Teck]

you can put a mark on the tire and on the drive shaft . Then jack it up and turn the tire one full turn and count how many times the drive shaft goes around to figure it out also.

 

[Avery4jc]

Don't you have to leave one on the ground and turn the other twice? Assuming it's open that is...

 

[obijuan]

with a 465 i bet its 3.73s but it could be anything. pull the cover and read the numbers. theyll tell you right there, you could probably stand to change the oil anyways.

oh and where did you find a k30 in round rock?!?!

 

[77_Jimmy]

Thanks for the replies guys. I figured it would be 3.73 or 4.10's. I drive tractor trailers around Austin at nite. It sat on the corner of 183 and Braker for 3 weeks. The owner said 1500 , I said 1200 , he said ok. It's been littering , I mean gracing my driveway since.

 

[Teck]

you might

 

[YZEATER]

you can put a mark on the tire and on the drive shaft . Then jack it up and turn the tire one full turn and count how many times the drive shaft goes around to figure it out also.

it's lift 1 tire off the ground, then rotate the tire 2 revolutions, and count how many times the pinion goes around.

 

[chulisohombre]

3.73 and 4.10 are the most common ratios i have seen on the 80s era 1 tons.as was said i would pull off the gear govers and just look and see what it looks like.always a good time to change the gear oil so you can see whats inside and know it is good.also cograts on the buy.1200 is a awesome deal if it runs.hell if you were just getting the axles it wouldnt be bad if they are in good shape.