Stock suspension

[Tyota89]

I have read the threads on stock suspension height from center hub to fender. Most 99s were sitting around 21" and other years around 19/20". I am sitting close to 22" all around.
So if I put a 2.5" lift on it does that mean I should do diff drop? Considering it is about an inch or two higher than the other years.

 

[absalom]

I don't recommend diff drops. The geometry of 99's aren't different, just the suspension. So replacing with 2.5" lift will net you less of a gain than other 4runners. Make sense?

 

[Tyota89]

Got it, so a 2.5 lift would be more like a 1.5". Don't know why I wasn't thinking that way.

 

[OkiSurf1996]

Depends what kind of lift. Springs/shocks will be less, but if you're planning spacer lift then it will be the 2.5".

 

[ShooterMcGavin]

I don't recommend diff drops. The geometry of 99's aren't different, just the suspension. So replacing with 2.5" lift will net you less of a gain than other 4runners. Make sense?

Would you explain why?

 

[absalom]

Would you explain why?

Some light reading and IIRC, they don't so much decrease the angle as they do change the angle. I guess the opinion I've formed over the years is, if your brand new, OEM boots are tearing, then your lift is too high. Used boots will usually tear after lift, as they are so "used" to being in one position.

 

[MTD]

Used boots will usually tear after lift, as they are so "used" to being in one position.

The used boots tear because rubber and other elastomers age and heat harden therefore the old boots tear quickly. The new boots do not tear right away because they haven't been hardened, but I agree they will fail much faster with a lift due to fatigue.

 

[JayRolla]

Some light reading and IIRC, they don't so much decrease the angle as they do change the angle. I guess the opinion I've formed over the years is, if your brand new, OEM boots are tearing, then your lift is too high. Used boots will usually tear after lift, as they are so "used" to being in one position.

Or you could stretch your boots then the lift does not kill them. Its because the angle causes them to rub and tear. Only limiting factor for to much front lift is excessive droop which will break the cv shafts and cause lower ball joint failure.

Diff drops are installed to help keep the angle down on the cv shaft so the joint last longer, not the boots.

 

[absalom]

The used boots tear because rubber and other elastomers age and heat harden therefore the old boots tear quickly. The new boots do not tear right away because they haven't been hardened, but I agree they will fail much faster with a lift due to fatigue.

I love learning new things each day.

Or you could stretch your boots then the lift does not kill them. Its because the angle causes them to rub and tear. Only limiting factor for to much front lift is excessive droop which will break the cv shafts and cause lower ball joint failure.

Diff drops are installed to help keep the angle down on the cv shaft so the joint last longer, not the boots.

Very good information here.

 

[snivilous]

Some light reading and IIRC, they don't so much decrease the angle as they do change the angle. I guess the opinion I've formed over the years is, if your brand new, OEM boots are tearing, then your lift is too high. Used boots will usually tear after lift, as they are so "used" to being in one position.

Don't worry, I agree they're fairly useless The diff drop marginally lowers the actual CV, and such a small angle change compared to the normal ride height angle and overall max capable deflection doesn't help enough to warrant one imo. Not that it doesn't help slightly, but I've never seen or experienced a CV failure (of the actual joint) that directly pointed to increased stresses of the joint. To each their own though, unless someone posts a stress analysis or failure test comparing a "normal" angled CV and "dropped" one it's all hypothesizing.