Any reason diff drops are only 1 inch

[theizzardking]

Just threw mine back on and noticed there's room for another half inch or so.

Is this a geometry thing or is it just standard to only make 1 inch rounds.

I also wish I would have gone with the tapered one ...I may just make my own and put a deep counter sink in it to help center the spacer.
They look cross eyed in there now ...

What's wrong with making a 1.5 inch spacer? Every fraction of an inch matters when your at the limits of ifs.

 

[brian2sun]

When you put the diff drop in, it mainly tilts the diff as opposed to actually dropping it. That tilting takes some of the pressure off the CVs, but it puts more pressure on the front driveshaft. 1" is a good happy medium. I have heard of people doing 1.5" drops, but I would not do it because I don't want the pinion angle to be too steep and ruin the bearing.

 

[theizzardking]

Hey thanks man ..binding issue with the front drive shaft ....you know of a thread were some fabbed or reworked their crossmember to truely drop it also if I go that route is the t case now vulnerable to strikes?

 

[J-money$$$]

Hey thanks man ..binding issue with the front drive shaft ....you know of a thread were some fabbed or reworked their crossmember to truely drop it also if I go that route is the t case now vulnerable to strikes?

if you drop the front differential how would that effect your transfercase clearance? If you think you could actually lower the transfercase you would have to drop the engine, and trans as well. Are you having some cv problems or what. If you want to do that heavy of modifying to keep your ifs you should seriously consider a sas. It would probably be easier.

 

[brian2sun]

Well, it'll be more vulnerable to damage since it'll be lower. I'm not sure if you would still be able to get a BudBuilt or a Skidrow skid on there, but if so that would take care of that issue. Dropping the whole thing (cutting the crossmember) may put just as much or even more stress on the front driveshaft, but I dunno. I've never seen it done in person. I'll stick with a 1" personally, I do not like the idea of weakening the crossmember to gain a measley 1/2".

 

[Singtoe]

If you lift your 4runner 3" then you should drop the diff At least 2" to keep the geometries the same as stock.

If the 4runner came with a CV jointed driveshaft, then swinging the Diff down would be no problem, but because Toyota uses U-joints, The pinion angle has to be parallel to the output shaft of the transfer case. If the Angles aren't parallel then the rotation speeds will vary from the output shaft to input shaft.

I brought up a suggestion to some one else about fabbing a drop kit so we will see if that pans out.

On a side note, people C channel out frames all the time to lower trucks. I think cutting out the cross member, dropping the diff and then making a new crossmember out of plate steel and bolt it up the frame could totally be doable.

 

[brian2sun]

If you lift your 4runner 3" then you should drop the diff At least 2" to keep the geometries the same as stock.

It's impossible to keep the geometry the same as stock when you lift an IFS. If you lift it, the CV angles change. If you drop the diff to compensate, the driveshaft angle changes. You must "rob Peter to pay Paul" if you know what I mean. Actually dropping the diff (as opposed to rotating it) and making it more susceptable to rock damage while weakening the crossmember is not a good trade off to save CVs. I have no issues with my CVs and 1" diff drop. IMO it is the happy medium.

 

[theizzardking]

Brain's right on the money as usual ...on all accounts...I should quit trying to reinvent the wheel and just go with the flow I guess...maybe a custom drive shaft...lol

 

[96743runner]

When you put the diff drop in, it mainly tilts the diff as opposed to actually dropping it. That tilting takes some of the pressure off the CVs, but it puts more pressure on the front driveshaft. 1" is a good happy medium. I have heard of people doing 1.5" drops, but I would not do it because I don't want the pinion angle to be too steep and ruin the bearing.

Ahhh that makes sense. I've been wondering the same thing for some time but never asked because I thought the answer was obvious. lol

 

[Gerdo]

You can only "drop" or rotate the front diff so far because it sits above the crossmember. 1" should work on every 4runner. I know that some people have added a few washers to drop it a little more. Just watch the ADD and stuff on that crossmember. leave some room for movement. You don't want to pop something loose because you wanted an extra 1/4"!

Read this Do diff drops actualy change CV angles? - YotaTech Forums my post (#21) explains the diff rotation/drop measurements.