How can i tell what 3rd member is used on my truck? The guy i bought it from say something about the 3rd member was replace a long time ago. I just want to know what he install.... any ideas?

 

also, someone i know have an 80 pickup. I was wondering if the 84-88 pickup 3rd member is the same. I was thinking on installing a 1 ton for it to tow...

 

Are you trying to figure out the ratio?

 

if you havent installed it count the teeth on the Ring and on pinion. if you have installed it then lift the truck up with one tire in the air, and rotate it 10 times, counting the number of times the drive shaft spins.

yes 79-95 8" thirds are interchangeable.

 

Thank you for answering so soon. Its great the its interchangeble.


I just want to know how many ton 3rd member i'm running. (3/4, 1ton, or 1/2ton)

Thats about all. Everything is installed. I dont really want to take it out unless if i really need to.


Curious....

 

make sure you're running the same gear ratio front and rear...........

 

If it is an 8" ring gear, then there is no difference in 3rd members (aside from gear ratio) between the various load rating axles:
- http://www.4crawler.com/4x4/4R_TechI...oDetermination

 

Google Toyota Differentials.. You'll be amazed I wish Toyota Diffs were one tons...

 

Sorry. I dont know so much about the 3rd members.

I need something that can pull a 20 foot boat. Before we had one that did fine. Until one day, the diff shot out some metal stuff.

we then bought a 1980 diff. It was a half ton truck or something. Now its not performing the same. Also the old one that shot out, it was BIGGER. this one is small...

Thanks for your help.

 

Toyota mini-truck diffs are sized by the ring gear diameter, you likely have a 7.5", the 4WD trucks and the larger (1 ton) 2WDs have the 8" ring gear:
- http://home.4x4wire.com/erik/diffs/

If the diffs are failing, figure out why. Usually the case of being run out of oil or using the wrong grade of gear oil (should be GL-5). Or the pinion flange loosens up and that lets the pinion bearings loosen up and the pinion gear starts walking all over the ring gear leading to chewed up teeth. For towing, you probably want something with a little lower gear ratio to get a little more pulling power. To keep a 5 lug axle and get an 8" ring gear diff, try and locate a junked 2WD pickup with that rear axle setup. Then you can swap over that entire rear axle and upgrade to the larger differential. I had a buddy with an '85 2WD pickup and his had the 8" rear diff even though it was just a regular 1/2 ton SWB model.

 

more background info would be nice...

year, model, 2wd/4x4, motor etc

 

Sorry.

1980 toyota pickup extended extra cab long bed. Running 22re 5 spd. 2wd.

Dont know what 3rd member.. tire size.. 185 70 14...

Thanks

 

hmmmm...unless you have a custom job..there was never a 1980 Toyota extended extra cab..
first toyota extend cab was 1984.
1980 would have rounded fenders. 1984 squarish fenders

efi was '85+

 

... I figured that. the model i have is an 1980. The old diff and rear brake parts was from a 1984 4x4. I just dont know what diff was on it. Some people told me it was a 1984 4runner 4x4. Never understand what it was really is. I might be able to pull out the diff number. somehow...