Rear shocks advise

[Juliank]

I have a 1998 4-door Tracker with 1.5" Boondox coil spacers and rear shocks from '91 Cown Victoria.

I have driven it like this for over a year with no noticeable change in the ride quality. The problem is I did not like the ride quality of the original setup to begin with. When I go through wholes or over bumps the suspension feels somehow loose, as if there is some play in the components, yet I do not see anything worn out. It is hard to describe, but it does not feel tight like on a new Jeep.

Last week I drove on a gravel road and I noticed that on uneven surfaces the truck tends to lose direction and I think this is coming from the rear. When it hits an uneven patch it tends to go to one side or the other. I had to drive much slower than the rest to feel safe.

I belive at least one of my shocks is not working well and I want to replace them and I need some advise:

1. Should I replace the springs as well? I can't understand why is this hype about aftermarket springs. The way I see it, the shock is the more important component in the suspension. What kind of improvement can one expect from a different spring alone (well, a bit more travel, but that's all I can see). I know the theory, I need someone with experience from real life to tell me.

2. Which brand of shocks should I choose. I read great things about EMU, but other people say they are middle quality and say Koni are the best. Are they really better and how is the difference noticed i real life?

3. I tend to buy Koni, but I don't know what model to order. I cannot order the stock one, as I have a 1.5" lift. They don't have a listing for Crown Vic. How can I chose the right size shock?

[MarkB.NV]

1. Check the rear trailing arms -especially the bushings on the mounts (both the frame and axle ends).
2. Check the upper axle mount. There is a tie-rod looking connector that ties the axle to the frame, just above the pumpkin.
3. Check the springs to see that they are not broken and are still attached correctly.

If any of these joints/bushings are broken, loose, worn-out, that could cause your symptoms.

I would expect that the shocks / springs are fine, unless you're jumping the truck

[Juliank]

I went and checked all that ( I had checked it before, but this time looked real good).

The bushings look good - no cracks, no wear. The rubber may have become softer, but visually they are OK.
The tierod visually is good, no play by hand, no leaks.
Springs look as new.

Only the shocks look greasy. I really suspect these shocks...

[Ole-Boy]

In the rear mainly, at the outer corners of the bumper (each side) give the bumper a good hard push downwards. Check for any bounce (generally works) If bounce, bad shock. Although in your case you mention they look greasy. Are there any signs anywhere of grease/oil close to the shocks? No, then I'd suspect they are bad. But usually (very rarely) both shocks don't go bad at the same time. Unless one of them were bad from the start, borderline bad. Could just be that the other one went bad and you're noticing a big change in ride.

What about a low tire? Bad bearings in the rear axle. I wonder if that could produce the symptom you describe?

I could be completley off in my assumptions too.

[relicduke]

What have you got for tires? Sometimes suspension gets blamed for weird stuff tires do

[jtgh]

sounds like unsprung weight issue.
try some new rear shocks.

Crown Vic

just buy some and pop em on . a 30m job, 4 bolts.

here, the topic never ends . on shocks
Set Search Parameters

[jtgh]

check that ball joint on the upper control arm of the rear axle pig
check the track arm ends for play.

compression dampening
rebound dampening.

whats right for your car and weight , depends.
some with drivnig pavement and wash board gravel roads.

also gravel is the worse , for tires. some like it . others hate ,it .

[Juliank]

Thanks for all tips. I will check all those points. I think at almost 300,000 km all of them are a bit tired and the small changes all add up.

I am more interested to know how much of a difference may some high end shocks and/or springs make over new stock ones. The people who sell them say the difference is day and night, but I am a bit skeptical. I did not notice ANY difference when i went from the stock shocks to the longer Crown Vic shocks and I suspect that if I go to OME the difference would be so small, I'd be disappointed. Perhaps replacing all suspension componets at the same time would make a pleasing difference. I just wonder if it is possible to make the Tracker ride like a limo on the highway and like an ATV on the gravel.

[jtgh]

be skeptical. they promise the moon and stars. and deliver zip.
the springs are just springs.
1: linear
2: progressives
3: rates.
linear springs ride like a truck but dont bottom out. On mine every inch of travel takes 76 more pounds of force, Linear and predictable.

Progressives , ride like Lincoln but bottom easy. (start at low spring rates and increase)
Rates. Low , good ride, high is bad ride (hard ) and carry more load, if high.
RATE is distance the spring moves at a given pressure (compressive)

once you decides what springs you want? (you can just get 4 dr springs and put it on 2dr)
the hardest factory springs are 4dr + 4wd. highest rate.

next is dampening.
the springs with out shocks , will oscillate. like like the little mexican dog you see in the rear window of some cars.

it will oscillate until they naturally dampen. which takes forever it seams..
so you decide to correct the oscillations.?

good.

you have 2 numbers. ( basic) (not counting stroke etc)
compressive dampening
rebound dampening.

compressive damping , higher is for racing to hold tire on ground and stop wheel hop over bumps
rebound dampening , slows the tires return to earth.
tuning of which is vastly complex. and depends on weight of :
car
axle
wheels.
speed
road surface.

probably the most complex subject matter on cars.

[Juliank]

From all I have read, this is the best explanation, which puts everything in the right spot.

So since I have the 4-door 4x4 springs as stock, I should stick with them. In the big scheme of aftermarket springs they must be somewhere in the middle - i.e. there are harder springs, which are for more load and softer progressives, which are for better ride and since I drive both on highways and gravel it makes sense to stay in the middle.

As for dampening - what would you recommend:
- OME shocks (which are longer than stock and will accomodate my 1.5" lift)
- Crown Vic shocks (which are long enough and cheaper)?
- Koni (not sure how to choose the right model from Koni)

I drive
90% highway, 8% gravel, 2% offroad.
90% one man only, 8% light load, 2% pulling a trailer