diff ratios

[mikeymud]

I have a ln130 surf with 1:4.55 diffs and I am looking at putting a solid front axle in it. I have found a front axle but it is 1:4.8 and the person who has it says it will match my rear diff. Is this correct?

[mud_slinger]

the front and rear diff need to match. so they are wrong, you will have to find a 4.8 rear diff the match.

[mikeymud]

Thats what I thought, but this guy seems to think it will work with my 4.5 rear. Thats not such a bad thing as I can get a 4.8 rear and my truck will go way better on the 35's with 4.8 diffs

[lax2wlg]

Up to .05 ratio variation front/rear is acceptable but not ideal. eg 4.875 rear, 4.88 front

If you were to run 4.8 front and 4.5 rear, one of them would fail catastrophically the first time you put it in 4x4. 2H will be fine.

But if Toyota gearsets are interchangeable you could still use the axle and get the SAS suspension/steering all set up, do gearing last.

[tweake]

just be carefull, 4.88 gears are not interchangeable afaik. they run a slightly different head. all others are interchangeable with factory and aftermarket gearsets.
if you want a strong diff fit aftermarket gears to your 4.5.

[mikeymud]

So it wont be possible for me to put the 4.8 diff head in my 4.5 housing? or even swap the crown and pinion gears?

[LOLYF]

a complete 4.8 head will bolt into the 4.5 housing no problem.

You can't put the 4.8 gears into a 4.5 head.

[tweake]

a complete 4.8 head will bolt into the 4.5 housing no problem.

You can't put the 4.8 gears into a 4.5 head.

as above.
also can't put aftermarket gears onto 4.8 head. so if your engine has a bit of grunt then it may pay to look at fitting aftermarket gears (as they are stronger than factory) to your 4.5 head.
or if your running 35's look at a 5.2 etc.

[vvilly]

I'm running 4.88's and 35's, and that brought my gearing back to standard. If you are going bigger in tyre I would run 5.29's.

[tweake]

I'm running 4.88's and 35's, and that brought my gearing back to standard. If you are going bigger in tyre I would run 5.29's.

what gearing and tires did you have as standard?

[suzolla]

So to summarise above from my understanding.
Toyota 4.88 ring gear is thinner than other ratios and the diff head is made to suit.
So Toyota 4.88 R & P will only fit Toyota 4.88 diff head.
Other ratios will not fit the Toyota 4.88 diff head.
After market 4.88 R & P will not fit Toyota 4.88 diff head but will fit other ratio diff heads.
All earlier Hilux and Surf 8" diff heads will fit Hilux or Surf solid axle housings, so will a High Pinion diff head unless it is an elec locker one.

Also I have got some Trail Gear 4.88 R & P's . If you are interested PM me

Cheers
Tim