Diff drop...Slee or BIOR?

[Live to Ski]

That over-extension of your friends suspension concerns me as related to a planned mild lift for my rig. One would think that any suspension lift "kit" would have built in limiting, or an optional purchase to address.

I have too little knowledge on the over-extension issue. Enlightenment for our rigs would be much appreciated.

 

[DirtDawg]

I do know of one instance where a friend of mine without a diff drop had just installed nitro upper control arms and icon shocks, he is only lifted about 2", he was driving through a ditch on his property to test out the new suspension and over extended his brand new oem cv which alowed it to bind up and snap. Would a diff drop have prevented this? Maybe, maybe not but another aspect to consider is if there is ever any plans to install extended travel suspension the cv may not be able to handle more travel without lowering the diff.

Being the only case of over extension I've ever heard of, why didn't he document the event on here? That would be very beneficial to the forum. But do you think the diff being lowered ~.85" would have changed that scenario? Sounds like he needed limit straps.

When I was cycling my front suspension during my lift install, I drooped the a-arms way lower than they would go with any lift (top bj disconnected), and I never saw any sort of over extension, though this was also static, whereas your friend was driving. But the cv working angle should be well within any lift's range.

 

[benc]

Being the only case of over extension I've ever heard of, why didn't he document the event on here? That would be very beneficial to the forum. But do you think the diff being lowered ~.85" would have changed that scenario? Sounds like he needed limit straps.

When I was cycling my front suspension during my lift install, I drooped the a-arms way lower than they would go with any lift (top bj disconnected), and I never saw any sort of over extension, though this was also static, whereas your friend was driving. But the cv working angle should be well within any lift's range.

Like I said, not sure if it would have prevented it or not but something to concider.
He may have documented it, I'm not sure. If you choose not to run a diff drop that is fine, I am simply stating the reasons why I ran it on mine to hopefully help others to make an educated decision. You will find that most on here that are lifted over 2" have the diff drop so it will likley be hard to find the proof your looking for.

 

[DirtDawg]

Like I said, not sure if it would have prevented it or not but something to concider.
He may have documented it, I'm not sure. If you choose not to run a diff drop that is fine, I am simply stating the reasons why I ran it on mine to hopefully help others to make an educated decision. You will find that most on here that are lifted over 2" have the diff drop so it will likley be hard to find the proof your looking for.

And I greatly appreciate the input. That's what I want this forum to be, an informative thread on choosing whether to run a diff drop or not. Not trying to prove anything, just want to cover all the points. I will be one of the data points for 2"+ lift without a diff drop, hopefully it doesn't come back to bite me in the butt

 

[LandCruiserPhil]

What is the hub to fender measurement you'all ya'll are calling 2" lift?

I have run 20.5 hub to fender for ever on a 99 and still run original boots. Never rebanded, replaced, or leaked. With that said both my 06 LC and 06 Lx470 boots leaked when raised to 20.5. Go figure given all 3 vehicles have never run a diff drop.

I do agree the geometry logically says a diff drop will reduce stress to the boot and CV. Personally my experience has shown its not enough to run out and install a diff drop and take on less clearance the diff drop offers.

One item not mentioned is the added torque steer without a diff drop but being part time its not an issue for me

 

[abuck99]

Upfront I'm at 21.5" which is roughly 2" to 2.25" over the original ride height I measured. The outer boots(closest to the wheel) are angled a bit but dropping the diff 3/4" wouldn't seem that it would improve it much. Ive read on the taco forum to stretch out the boot a little further down the axle and reclamp to keep the folds from rubbing on each other (if required).

and Phil, its "Ya'll"

 

[SWUtah]

I'm at 21.5" front and rear with diff drop. After the diff drop I now get 25 mpg

 

[Live to Ski]

SWUtah: Probably your added rake. Looking downhill all the time has gotta improve the illusion of better mpg

 

[LandCruiserPhil]

Put an end to leaking boots go part time

 

[Live to Ski]

So Phil, why would diff elevation affect torque steer?

My only knowledge related to torque steer has to do with different length axle shafts, and the associated difference in torque induce wind up (different lengths, different amount of wind up). Will the diff drop affect each length enough to really change the windup?

 

[LandCruiserPhil]

So Phil, why would diff elevation affect torque steer?

My only knowledge related to torque steer has to do with different length axle shafts, and the associated difference in torque induce wind up (different lengths, different amount of wind up). Will the diff drop affect each length enough to really change the windup?

The more angle of axle shafts the more torque you will feel.
The average 100 series owner does not relize the amount of torque steer they have until they drive with rear drive only. My LX470 is part time and the differance is clear, even by the wife.

 

[Live to Ski]

Ah, my education continues! Thanks.

 

[MobileBasecamp]

Hey everyone. May or may not get sympathy on this one, but installed the Slee diff drop last week and since then have had a few thing happen on a recurring basis. 1) Getting a creaking sound (almost) that I'm feeling a lot under my left foot while driving. It's audible on both sides of the car and front to back, is about steering wheel level. It comes around more frequently when I'm turning but also going straight, all the way up to 45 mph. 2) Also randomly seeing my RPM spike, though this isn't happening as frequently. Mostly when traveling at lower speeds, around 5-20 mph range.

I just got OEM Axle assemblies and with that investment was hoping that the diff drop would help "protect" my investment and give me more peace of mine since I've had CV issues strand us in bad places before (not the same rig). Just pissed because it was driving perfectly up until we installed this. Any help is really apprecaited!

 

[Biga27110]

Hey everyone. May or may not get sympathy on this one, but installed the Slee diff drop last week and since then have had a few thing happen on a recurring basis. 1) Getting a creaking sound (almost) that I'm feeling a lot under my left foot while driving. It's audible on both sides of the car and front to back, is about steering wheel level. It comes around more frequently when I'm turning but also going straight, all the way up to 45 mph. 2) Also randomly seeing my RPM spike, though this isn't happening as frequently. Mostly when traveling at lower speeds, around 5-20 mph range.

I just got OEM Axle assemblies and with that investment was hoping that the diff drop would help "protect" my investment and give me more peace of mine since I've had CV issues strand us in bad places before (not the same rig). Just pissed because it was driving perfectly up until we installed this. Any help is really apprecaited!

Mine started doing something similar on the driver side only and not as consistently. Would love to figure it out maybe its the sliders?

 

[MobileBasecamp]

Mine started doing something similar on the driver side only and not as consistently. Would love to figure it out maybe its the sliders?

I feel it on the drivers side for sure, but it can just be heard well from either side. How long have you been driving with it like that?

 

[Biga27110]

I feel it on the drivers side for sure, but it can just be heard well from either side. How long have you been driving with it like that?

3 weeks, i dont have a diff drop. I just ordered one thinking it might help lol