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vcross62
03/28/2012, 12:05 PM
Hi everyone,

I am new to this forum. I bought a used Isuzu Vehicross 6 months ago. When i test drive the car before i bought it i already realize the vehicross is a really bumpy car and i was told by the car salesman that the absorbers has already kaput and if i replace them it wouldn't be that bad. I bought the car and replaced all four absorbers, it does improve but the car is still very bumpy and i mean really bumpy. When i drive over road bumps i would puke! that's how bad it is.

Is that normal for a vehicross? Also any one here modded the absorbers or suspension to make the vehicross less bumpy? Another issue here with my vehicross is the engine has 3200cc but it doesn't accelerate like one. Is there an issue with my car or it's just normal? Any advise would be appreciated.

Thank you
Eugin

circmand
03/28/2012, 12:16 PM
The ride is a bit rough as its a truck not a car. Many on here have put on adjustable shocks and set it for their preference. Also a nice trickis cutting a bit of the bumper stops so the ride smooths out. AFAIK the VX came with a 3.2 or 3.5 engine no idea about the 3200cc

BigSwede
03/28/2012, 01:05 PM
3200 cc = 3.2L

That durn metric system... :grino:

Ala5ka
03/28/2012, 01:25 PM
Yep cut the "anti-roll" rubber bumpers (can't call em bump stops since they technically aren't haha) they look like a rubber "8" on top of the back axle, cut them till they are just an "o". Some may say otherwise but I've been driving without the front sway bar for some time now and I think that helps a lot on speed bumps and the body roll isn't bad at all. Expect a rough ride on the road at the same time a Cadillac vs the VX on a fire road shows that ride quality is only determined by how the road decides to behave :)

89Vette
03/28/2012, 03:15 PM
i was told by the car salesman that the absorbers has already kaput and if i replace them it wouldn't be that bad.

Whatever it takes to sell a car!

:sighb:

VX KAT
03/28/2012, 04:15 PM
This exact topic has been discussed MANY times here. I put several of these posts together for reference. Sorry for the long post, but there's lots of info on this.

You NEED to read up on this so you'll better understand what others have tried, what worked, what didn't, etc....

The bottom line....the VX is NEVER going to be anything near a smooth ride on dirt/gravel/rocky roads....NEVER..no matter what you do.
I live on a dirt/rocky/rough road....I have the 9 way adjustable Rancho shocks...even set on the "softest" setting, the ride on the dirt road, and particularly on WASHBOARD/ruts....is really rough.

The softer shocks "help" some, but my steering wheel still vibrates like heck, and my tailgate door vibrates SO MUCH I have to have my hatch popper thing re-aligned about every 3 months, as the strong rough vibrations actually jiggle it loose. Also, my empty passenger seat seatback vibrates so much I'm afraid it's going to possibly break something over time.

To clarify what "Ala5ka" said in post #4...some people call the rubber part a "bump stop" and some call it a "spring helper".....Isuzu actually uses both terms in the part listing. I've attached a few pics of them. Some of us have cut the bump stop in half, allowing for about 4" MORE travel room before the rear axle hits the bump stop. It "improves" the slamming/jolt effect that you hear and feel from the rear axle going over rough roads. It is a only a little improvement, but I think it's worth it. You can always buy replacements from a junk yard or aftermarket ones if you want to go back.
.


ADDRESSES TERMINOLOGY "SPRING HELPER" VS. "BUMP STOPS", ALSO COIL COMPRESSION, ROLE OF SPRINGS, PARTS DIAGRAM:
http://www.vehicross.info/forums/showpost.php?p=244328&postcount=10


COMPLETE THREAD WHERE POST #10 CAME FROM:
http://www.vehicross.info/forums/showthread.php?t=21549&highlight=bump+stops+half


BUMP STOP QUESTION, GOOD TECHNICAL DETAILS:
http://www.vehicross.info/forums/showthread.php?t=19217&highlight=bump+stop


THREAD ABOUT "STIFF RIDE"
http://vehicross.info/forums/showthread.php?t=19628&highlight=bumpstops


The rear bump stop is the black rubber thing immediately to the right of the spring. It's a side view, but it's like a figure "8", with the BEIGE color stuff (dirt) at the bottom of the "8" TOUCHING THE AXLE...So almost no room for the REAR axle to move w/o hitting the bump stop immediately....causing that really loud SLAMMING JOLT
http://i1099.photobucket.com/albums/g386/photokat4/MISC%20VX%20PICTURES/DSCN0435-1.jpg


Here's 2 pics of mine after cutting the lower half of the "8" off.....see how I gained about 4" of room.
http://i1099.photobucket.com/albums/g386/photokat4/MISC%20VX%20PICTURES/0908111658b.jpg

http://i1099.photobucket.com/albums/g386/photokat4/MISC%20VX%20PICTURES/0908111649d.jpg

blacksambo
03/28/2012, 08:20 PM
If you cut them you will reduce the vehicle's roll resistance, and also increase road noise considerably. FYI.

VX KAT
03/28/2012, 08:25 PM
If you cut them you will reduce the vehicle's roll resistance, and also increase road noise considerably. FYI.

:_thinking How do you know either of these? :_thinking
I've had mine done for almost 2 years, and I can def say it's a little more quiet because the slamming jolt noise is greatly reduced....and I seriously don't notice ANY increase in general road noise.

How does LESS contact between the bump stop and the axle REDUCE rolling resistance? if anything, I'd think it would be the opposite....:_thinking

PK
03/28/2012, 09:22 PM
I cannot see how you would increase road noise by cutting the bump stops, until the springs compresses enough to hit the cut stop.

But I have to agree that it will increase body roll when cornering.
Anyone with cut stops that has not experienced more body roll, just aint trying hard enough.

At that is why I will never cut my stops.

PK

VX KAT
03/28/2012, 09:42 PM
I cannot see how you would increase road noise by cutting the bump stops, until the springs compresses enough to hit the cut stop.

But I have to agree that it will increase body roll when cornering.
Anyone with cut stops that has not experienced more body roll, just aint trying hard enough.

At that is why I will never cut my stops.

PK

Oh, Sambo said "roll resistance" I thought he was meaning "rolling resistance"....you know the tire and their various compounds and how sticky they are or are not.....geez Sambo you usually are very particular about people using the correct terminology....I think the more common term is what PK said..."body roll".


PK, gotta agree....I ain't tryin' hard enough to worry about body roll...:laugho:...I'd gladly sacrifice that for the "improved" ride (such that it is :goof:) with the stops cut in half. Plus it's not permanent....all I got to do is buy replacements.
Guess it all comes down to an individual owner's needs/wants/tolerance..etc.....

circmand
03/29/2012, 05:31 AM
To clarify what "Ala5ka" said in post #4...some people call the rubber part a "bump stop" and some call it a "spring helper".....Isuzu actually uses both terms in the part listing. I've attached a few pics of them. Some of us have cut the bump stop in half, allowing for about 4" MORE travel room before the rear axle hits the bump stop. It "improves" the slamming/jolt effect that you hear and feel from the rear axle going over rough roads. It is a only a little improvement, but I think it's worth it. You can always buy replacements from a junk yard or aftermarket ones if you want to go back.
.


How do you get 4 more inches? Since the part is rubber abd it has open spaces in it I assume the stop doesn't really stop. I would think it slows by compressing and only stopping once the stop is compressed so that the open area dissappears. I would think cutting half off only gives you the extra equivilent to the size of the amount of rubber minus the open area.

VX KAT
03/29/2012, 09:01 AM
How do you get 4 more inches? Since the part is rubber abd it has open spaces in it I assume the stop doesn't really stop. I would think it slows by compressing and only stopping once the stop is compressed so that the open area dissappears. I would think cutting half off only gives you the extra equivilent to the size of the amount of rubber minus the open area.

that's what he said......:slap:


The rubber stop is very hard rubber, and not meant to compress that much at all....just enough to protect metal on metal contact....thus the violent slamming jolt....not much compression.

So it may not be a full 4" but it's enough to drastically reduce the number of times that stop hits my axle in my driving conditions and environment.

It does NOT appear to me in the pics that they've had 10 years of flexing laterally i.e. squishing the empty space which would cause the sides of the 8 to move outward some and be compressed on themselves (the smooth inner lining of each "O" would touch each other at full compression). I would think the rubber would show significant deterioration and splitting on the sides of the 8 from all that compression over and over.

Again, from the pics, they don't look like they've ever touched at all. Mav and the other gang that have cut them and seen the old stops in person maybe could describe the condition better.

blacksambo
03/29/2012, 09:29 AM
How do I know about the noise factor? If you recall, way back when I started this discussion, my spring helpers were completely MIA. The only thing left was the mounting plates and bolts. So I phoned Merlin right up and for $48.00/each I got two new ones. I put them on, and voila the truck was quieter going down the road. Even my wife, with out prompting, said what did you do to quiet things down. So, that's how we know. Before versus after, it's simple.

Scott Larson
03/29/2012, 10:41 AM
So, they are also driveline and/or suspension vibration dampers...Hmmmmm, very interesting...

VX KAT
03/29/2012, 11:38 AM
How do I know about the noise factor? If you recall, way back when I started this discussion, my spring helpers were completely MIA. The only thing left was the mounting plates and bolts. So I phoned Merlin right up and for $48.00/each I got two new ones. I put them on, and voila the truck was quieter going down the road. Even my wife, with out prompting, said what did you do to quiet things down. So, that's how we know. Before versus after, it's simple.

Is it possible the "before" noise was the mounting plate hitting the axle, or was it some other type of noise that was reduced?

If that's the case, I can see where FULL or SHORTENED bump stops would def decrease (darn near eliminate) some noise in your scenario where you had no rubber stops at all.


Interesting how they're called different things on the parts' sites, but the pics confirm same part.


MERLIN'S ST.CHARLES WEBSITE
[ 3 ] REAR SUSPENSION / REAR SUSPENSION / SUSPENSION COMPONENTS / Damper
damper Left

MSRP Core ? Online Price
$52.02 $0.00 $44.22

[ 3 ] REAR SUSPENSION / REAR SUSPENSION / SUSPENSION COMPONENTS / Damper
damper Right

MSRP Core ? Online Price
$52.02 $0.00 $44.22

***************************************

MYISUZUPARTS.COM
163 RUBBER; HELPER,RR SPR 8-94374-448-1 2 12-1998 and LATER
VEHICLE OPTIONS: DOOR SHORT


***************************************

ISUZUPARTS.COM
Bumper
Vehicross
List Price : $52.02
Your Price : $41.62
Quantity:

vt_maverick
03/29/2012, 12:21 PM
If you cut them you will reduce the vehicle's roll resistance, and also increase road noise considerably. FYI.


How do I know about the noise factor? If you recall, way back when I started this discussion, my spring helpers were completely MIA. The only thing left was the mounting plates and bolts. So I phoned Merlin right up and for $48.00/each I got two new ones. I put them on, and voila the truck was quieter going down the road. Even my wife, with out prompting, said what did you do to quiet things down. So, that's how we know. Before versus after, it's simple.

I agree on the roll resistance issue, not only is it perfectly explainable (there's nothing there for the vehicle to lean on through turns) but I have driven my VX hard enough to tell the difference now that I've cut the stops. I've been debating putting the stock dampers/helpers/stops on since I now have the 1.5" Daystar spacers to soften the bumps. It is a little scary at high speed...

On the other hand I've cut the stops in two different VX's now and can tell you that in my "before versus after" experience there is no increase in road noise whatsoever. The only thing I can figure is perhaps you were hearing your suspension travel more, which for some reason is noisy on your VX?

VXorado
03/29/2012, 01:01 PM
I agree on the roll resistance issue, not only is it perfectly explainable (there's nothing there for the vehicle to lean on through turns) but I have driven my VX hard enough to tell the difference now that I've cut the stops. I've been debating putting the stock dampers/helpers/stops on since I now have the 1.5" Daystar spacers to soften the bumps. It is a little scary at high speed...


All about your springs. The stock springs are a little too spongy to add lift and chop the bump stops without creating more body roll. The 913 coil springs would help your VX feel more stable with the bumps chopped.

I only get a little body roll on hard turns with 919 coil springs, no rear sway bar & chopped bump stops. I remember having handling issues when I had 1" spacers on my stock coil springs.

blacksambo
03/29/2012, 02:10 PM
I agree on the roll resistance issue, not only is it perfectly explainable (there's nothing there for the vehicle to lean on through turns) but I have driven my VX hard enough to tell the difference now that I've cut the stops. I've been debating putting the stock dampers/helpers/stops on since I now have the 1.5" Daystar spacers to soften the bumps. It is a little scary at high speed...

On the other hand I've cut the stops in two different VX's now and can tell you that in my "before versus after" experience there is no increase in road noise whatsoever. The only thing I can figure is perhaps you were hearing your suspension travel more, which for some reason is noisy on your VX?

Well, I attribute the noise abatement to the fact that the VX pretty much rides on the spring helpers, once in motion. If you check the phantom view in the JDM brochure you'll see that the spring helper almost barely touches the rest pad when stationary. In motion, everything would have to compress turning the helper into deadening device.

Scott Larson
03/29/2012, 04:00 PM
Bingo!! :slap:

Kong
06/15/2012, 09:11 AM
I just bought my VX in April 2012, originally it was in silver and I painted it to solid red. I met you once in elite highway during my trip to the south.
Same to you, i stay in Klang!
May I know how much you bought the car?

VX KAT
06/15/2012, 11:12 AM
I just bought my VX in April 2012, originally it was in silver and I painted it to solid red. I met you once in elite highway during my trip to the south.
Same to you, i stay in Klang!
May I know how much you bought the car?

:_thinking....who are you directing your questions/comments to?

eblank
06/15/2012, 11:49 AM
Is it possible that our spring helpers have simply worn out over 11-13 years and gotten stiffer? Any comments from original owners? I started with stock springs and went to OME 912's and get the same jaring with both of them making me think that my helpers were never sitting directly on the axle (but that's just a guess...) I get their purpose but they just seem way to stiff. I'd like to cut them but I might try new shocks first and see what that does.

VX KAT
06/15/2012, 12:00 PM
I'd like to cut them but I might try new shocks first and see what that does.

Many of us have replaced the OEMs with adjustable shocks (Rancho 9000XL 9 way adjustable) and they did help the overall roughness a bit, but really had little effect, if anything, on the slamming in the rear. Even on the softest setting, I'd get the hard slam, but I then had the floating effect, every time I had to stop....like your grandfather's land yacht from the 60s ...boing boing boing....

SilverBullet75
06/15/2012, 05:20 PM
I lifted with OME 919s and have stock shocks. LOVE the feel of the rear. Also, much taller and more travel...

Kong
06/16/2012, 08:34 AM
I sent my VX for auto foaming this morning. Auto foaming is to apply foam into the hollow sections of the cars body & chassis members. It helps a lot on my VX handling also reduce noise and bumpy ride feeling.
Please refer www.autofoam.com.my

VX KAT
06/16/2012, 09:26 AM
I sent my VX for auto foaming this morning. Auto foaming is to apply foam into the hollow sections of the cars body & chassis members. It helps a lot on my VX handling also reduce noise and bumpy ride feeling.
Please refer www.autofoam.com.my

interesting, never heard of it. Looks like it's more for soundproofing rather than suspension damping /reduction. How would it be strong/stout enough to actually damp the suspension/vibration/movement of the 4,100 lb truck?

89Vette
06/16/2012, 01:02 PM
Sound dampening, yes. Suspension changes, no.

New to forum, lack of meaningful reply, posting links = spammer.

Kong
06/17/2012, 08:18 AM
Before i foam my VX,I was also thought that foaming is only for sound dampening. However, when I reached the foaming workshop, saw one continental car (mercedes c class year 2012) was prepare for foaming as well.
The owner said it was his second Mercedes sent for foaming, the first one done a month ago, and this was for his wife.
I was told by him foaming actually improve car handling. Imagine a hollow bar compare to a filled bar, which is more rigid? The rigidity actually affecting the shaking condition.
After trying on my foamed VX, I would said.....I agree, foamed car is having better handling.
I just share my experience for reference....

mantis465
06/17/2012, 04:16 PM
Before i foam my VX,I was also thought that foaming is only for sound dampening. However, when I reached the foaming workshop, saw one continental car (Mercedes c class year 2012) was prepare for foaming as well.
The owner said it was his second Mercedes sent for foaming, the first one done a month ago, and this was for his wife.
I was told by him foaming actually improve car handling. Imagine a hollow bar compare to a filled bar, which is more rigid? The rigidity actually affecting the shaking condition.
After trying on my foamed VX, I would said.....I agree, foamed car is having better handling.
I just share my experience for reference....

the Mercedes is a unibody construction, and i could see foam injection possible improving body rigidity in that and changing handling characteristics. the vx is a full frame truck and injecting foam into the body would do nothing for the handling as the body and frame of vehicle are separate unlike unibody were the body is the frame.. i am sorry but i would have to strong disagree with you on your claims for the vx