Topic: ring and pinion ratio question

[Ozy]

what would happen if I had 4:30 to 1 in the front and 4:10 to 1 in the rear?

I broke my front 3rd and bought a used one. I took the sellers word that it was 4:10 to 1 but kooked out and didn't count the teeth on the gears when I had the chance.  I have had it in 4WD in the dirt and snow since and there were no problems but on the street it acted really funny, which is why I'm not sure if the ratios are the same

[79coyotefrg]

what can happen you ask??  you can blow your tcase apart.

get on a gravel road (so you dont have full traction) have someone slowly drive forward in 4wd while you closely watch the tired front and rear, if its 4.30's in front and 4.10's in the rear the fronts will be trying to slide  and the back will try to spin

[kneedownnate]

Don't run it in 4wd on the street    I have a 4.37 front and 4.30 rear and it even feels like it's binding on dirt or in the snow.

[emsvitil]

If there's no locker or limited slip up front:

1.   Leave transfer in 2wd
2.   Jack up one wheel and spin tire 2 full turns.
3.   Count how many times the driveshaft turns.
3a.    4.10, It should turn just slightly less than 4 1/8 times
3b     4.30, It should turn just slightly more than 4 1/4 times

If you have a locker or limit slip; You'll need to jack up the front end, not just 1 wheel and turn both wheels at the same time 1 full turn.
Then the values will be:
3c     4.10  Just slightly less than 4  1/8 times
3d     4.30  Just slightly more than 4 1/4 times.

[axled89]

BOOM!!    they need to match.

[potter85]

having the wrong ratios in the front and rear is really bad... it puts everything in a bind putting way more stress on everything

[axled89]

hey man there's someone on parts wanted. that is looking for a 4.30 ratio,  maybe get it to them .
  then you won't be so screwed.

[Ozy [OP]]

Thank you to all who replied. I jacked one wheel up and checked and it appears that both front and back are the same.

[Ozy [OP]]

Question: did Toyota ever make an IFS truck/4runner with 4.11 to 1 ring and pinion?

thanks again for the help

[Rocksurfer]

A real easy backyard way to find out if the diffs are matched is simple. Just put it on a flat level (or close to it) surface, lock in the hubs, put it in 4wd, trans in neutral and push it by hand gently forward. If they match there will be no resistance if not it will take less than one revolution of the tires for it to start to bind. Don't even try to move it under power in 4wd or with the hubs locked until you find out it would be real ugly.

[Ozy [OP]]

A real easy backyard way to find out if the diffs are matched is simple. Just put it on a flat level (or close to it) surface, lock in the hubs, put it in 4wd, trans in neutral and push it by hand gently forward. If they match there will be no resistance if not it will take less than one revolution of the tires for it to start to bind. Don't even try to move it under power in 4wd or with the hubs locked until you find out it would be real ugly.

Thanks, I'll try this.

I only had it in 4wd on pavement once and it felt like the front end was getting pulled down then it wanted to veer to the left - it did this exact same thing a number of times and I stopped and unlocked the hubs. I haven't had it in 4wd on pavement since