IÆm inclined to agree [ * No boat ramp pun intended * ]
At the very least, having more traction certainly wouldnÆt hurt.

(Besides, you wanted to add a locker or two anyway, right? <img src="/forums/images/graemlins/smile.gif" alt="" /> )





No problem, Mike...
I've heard that (perhaps) some 1995.5 Rodeos got the equal-length CV Shafts - but it might just be a rumor...

With that said - just in case, letÆs pretend that I typed '1996 - 1997' <img src="/forums/images/graemlins/wink.gif" alt="" />


<img src="/forums/images/graemlins/cheers.gif" alt="" />
<img src="/forums/images/graemlins/smile.gif" alt="" />

Yea ok a locker or two would help quite a bit even though I pulled the same boat out of the water two weeks ago (while the Zu was getting tranny flushed, filter change, etc..) with my Lexus 470 (Glorified Land Cruiser) it has full electric lockers all around and it will still spin the tires on the way out. Wet tread + Wet concrete + decent angle = tire slippage or at least on my boat ramp! <img src="/forums/images/graemlins/smile.gif" alt="" />

Maybe I got a little off track with only giving an example of my wheel hop trying to pull my boat out of the water... Even on flat dry land in 4wd (pulling the boat) the front end will "hop" with no extreme amount of power applied (Just enough to cruise 50 yards to my driveway). I can somewhat understand the anti-squat deal (have to go out and look at it to really visualize) I'll try to post some pics tonight on the angle on my CVs maybe I'm looking at this all wrong.. .Thanks so much for ur input! <img src="/forums/images/graemlins/cheers.gif" alt="" />

This is long enough for a couple of posts... so lemme speak to range of motion, bumpstops, and front IFS first.

On other Isuzus (with long or short A-arms), I've seen the 'bounce' happen when the truck is lifted to an extreme.

Here's the truck's approximate rideheight stock:
[color:"blue"]*bumpstop*-------------------------[color:"red"]*rideheight*[/color]-------------------------*bumpstop*[/color]
So actual travel looks something like this:
[color:"blue"]*bumpstop*------[color:"orange"]*travel*travel*travel*travel*travel*travel*travel*[/color]------*bumpstop*[/color]
Note that in factory configuration, you will hardly EVER hit the bumpstops, unless you overload the vehicle or jump it.

...and here's what it looks like with a little lift:
[color:"blue"]*bumpstop*------------------[color:"red"]*rideheight*[/color]--------------------------------*bumpstop*[/color]
So actual travel looks something like this:
[color:"blue"]*bumpstop[color:"orange"]*travel*travel*travel*travel*travel*travel*travel*[/color]-------------*bumpstop*[/color]
In this case, at the extremes of travel, you'll find yourself up against the lower bumpstops.

Now roll in a LOT of lift:
[color:"blue"]*bumpstop*--------[color:"red"]*rideheight*[/color]------------------------------------------*bumpstop*[/color]
So actual travel looks something like this:
[color:"blue"]*bumpstop[color:"orange"]*travel**travel**travel**travel**travel*[/color]-----------------------*bumpstop*[/color]
With a lot of lift, you're pretty close to the bumpstops at normal ride height, and you'll feel them over mid-sized bumps. You'll have reduced range of travel (only 5 'travel's as opposed to 7 'travel's above) since you're hitting those stops... and coming off speed bumps and such, your wheels may occasionally lose contract with the ground, since ths suspension is stopped by the bumpstops.

Here's what TOO MUCH lift looks like:
[color:"blue"]*bumpstop*[color:"red"]*rideheight*[/color]--------------------------------------------------*bumpstop*[/color]
So actual travel looks something like this:
[color:"blue"]*bumpstop[color:"orange"]*travel**travel**travel**travel*[/color]-------------------------------*bumpstop*[/color]
In this example, you are essentially riding on the bumpstops. You have uptravel, but no downtravel, so coming off any bumps, the wheels cannot follow the ground, and you will be 'hopping' around. This is pretty dangerous, especially on the front end; while traversing bumpy turns, your front wheels will <img src="/forums/images/graemlins/scared.gif" alt="" /> LEAVE THE GROUND <img src="/forums/images/graemlins/scared.gif" alt="" /> and the truck will want to go straight, regardless of your steering input. In this case, there is still more reduced range of travel (only 4 'travel's as opposed to 5 or 7 'travel's above) since you're almost always on the stops...
Incidentally, it is possible to keep cranking the T-bars and actually tension the suspension into the bumpstops (cirtually guaranteeing later failure, IMHO) and further reduce the uptravel, since you're preloading the T-bar not to move away from the bumpstop.

Where you fit withing these examples, I can't say, but you'll have to balance suspension travel with the amount of lift, and make your own compromise based on your own usage, always with safety in mind. Many years ago, I ran far more lift than I today feel comfortable with. Apparently I'm (getting?) old. <img src="/forums/images/graemlins/zombie.gif" alt="" />

Randii

With that general background on range of motion, bumpstops, and front IFS out of the way, let's talk about YOUR truck.


Let me break out three different things, here:
* CV angles
* front suspension travel
* angularity on rear links due to lift
All of these things compound as a result of having lots of lift, but bnold, as I sit here several thousand miles away, I believe your 'bouncing' problem is more a result of where your front suspension is set to, relative to the limits of travel, than the other issues. It might help to think of them separately, even though they are at least somewhat related.

On other Isuzus (with long or short A-arms), I've seen the 'bounce' happen when the truck is lifted to an extreme. What sort of room do you have between your A-arms and the lower bumpstops?

Randii

Just as a note, this is the first IFS I have dealt with, after putting on the 912 springs and cranking the t-bars, the CV angle is not as extreme as I would have thought. BTW I have a 02 passport. IT definitly looks like I could go higher. Also it has been a month now and no cv problems yet, (knock on wood.) Also the change in the camber caster was no where near as extreme as I would have thought either. this may be due to the longer a arms you all where talking about.

Ok well I took pics to give u guys a better visual but im not quite sure how to upload the files... I measured the distances from the bumpstops while I was under there and came up with the following:

Unloaded:
1.5" from top
1.75" from bottom

Loaded with Boat trailer:
1" from top
2.25" from bottom

Does this sound about right or am I cranked to high <img src="/forums/images/graemlins/confused.gif" alt="" />?? I have the pics if someone would like to see them maybe in an e-mail?? (I can handle an attachment lol!)

Send them to me... I'll host and post them for you:

sstrawmyer@yahoo.com

I just sent u an email thanks <img src="/forums/images/graemlins/cheers.gif" alt="" />

Here are the pics:





I resized them so they wouldn't be 21" wide <img src="/forums/images/graemlins/wink.gif" alt="" /> If I need to blow them back up some, just let me know. Should be big enough, though.

<See additional post below -- my mind was confusing simply dropping the diff with drop bracketry for the whole a-arm assembly, even though I knew damn well we weren't talking about dropping the whole assembly... So MOST of this post would be more of a reference to a Chevy IFS style drop bracketry lift...>

This picture shows the reason the drop diff hasn't been used on the 98+ Rodeo/Amigo/RS yet -- and it's not the CV's. It's those other sets of bellows in the pic, the ones attached to the Rack & Pinion steering, outside of the photo to the right. This particular Rack & Pinion has a serious weakness if allowed to droop too far to the extremes of travel. Several people running 33's and above have bent their droop stops (very weak on the 98+ trucks) and subsequently blown their rack. If I recall correctly, it's $188 from Isuzu (St. Charles I believe) but I could be wrong. I never replaced mine but it was leaking and about to go when I got rid of the truck. Corbin Cowan replaced his several times. Tho I can't remember exactly who, I know several others had to replace theirs.

That being said, dropping the diff would allow for additional downtravel, beyond the scope of the original design for the steering rack, and therefore would likely blow out the rack. Of course, the rack could be dropped an equivalent amount, however, this is not a particularly easy task. The rack mounts ABOVE the frame rails, so the only way to drop it would be to put it UNDER the frame, which of course leads to a dizzying amount of additional fabrication. Not to mention the fact that the frame in that area is somewhere around 4 inches tall, so it would be a drop of 4 inches. You'd have to match that with a diff drop of 4 inches, otherwise the uptravel would likely blow out the steering rack as well.

As you can see this could be done with the right amount of perseverance and fabrication skills, but by the time you did all this, wouldn't it be easier to just swap in a solid axle? If you have the fabrication skills to do all of the above with the rack, swapping in a solid axle with coilovers and full hydraulic steering would be like child's play. <img src="/forums/images/graemlins/wink.gif" alt="" />

Now, that being said, if you could figure out the extreme lower limit of the steering rack, you could drop the diff only that much... Or you could limit the droop to a point that wouldn't harm the rack, but the whole point of this is to increase downtravel, right? Probably the easiest option (but one of the more expensive) would be for someone to machine up replacement tie-rods for the steering rack which would be longer... Problem is, Isuzu calls this a non-serviceable part, so there's not a good chance you'd find anyone willing to take this thing apart, design, tool, and machine up the parts, and put it back together without any problems... But then again, money makes the world go round, and some people love a challenge. <img src="/forums/images/graemlins/wink.gif" alt="" />

Anyway, just wanted to point out probably the most important reason not to drop the diff on the 98+... And point out a bunch of options for those people more ambitious than me -- when you make it, I'll buy it...

<img src="/forums/images/graemlins/smile.gif" alt="" />

-Chris