tns1

The CD on my 98 4RnR ltd was skipping over the slightest bumps. I saw a post by ^voodoo^ about the internal shocks wearing out and decided to investigate. What I found was that the CD drive plate is suspended by six small coil springs, and its motion is damped by 3 high-tech oil-filled silicone bladders, two in the back and one in the front where the CD loads.

I found my CD unit had a few problems. The drive plate sagged slightly due to tired springs, and the front damper was blown, allowing the front of the drive plate to bounce too far up and down. There was also evidence of metal-to-metal interference when the drive plate swung too far to one side. My fix was to raise the sagging drive plate with some extra springs, restore the damper by packing it with wheel bearing grease, and trimming a small metal corner to allow more side-to-side travel.

It may be possible to get by with just the spring fix, which is not that hard.

PIC1
This is the back of my 2DIN HU. The top plate comes off with just 2 screws.

PIC2
After you remove the front bezel, (unsnaps at about 10 places), you can see how the CD sits. You must have already loaded a CD prior to dissassembly or the internal drive plate which holds the CD, motor, and laser assy will be rigidly locked in place and not freely suspended by the spring mounts. With the drive plate floating freely, it should hold the CD centered in the front slot or slightly above the mid-point. Too high, or worse too low, and the CD will strike metal when you go over bumps. This pic was taken after the fix and looks good.

Next check the suspension damping by jostling the whole unit. If its like mine was it won't take much for the CD to bottom out against the insertion plate. This was mainly because the front damper was shot.

If you need to be convinced, do this while playing the CD in your car. You will have to partly dissasemble the front bezel to get the dust filter out of the way. You can then snap the bezel back on and still see into the loading slot.

PIC3,4
These blurry pics show the copper colored springs I added, one on each side. I put them on the same mounts with the stock springs. I happened to have an assorted spring kit, but if you take apart some old ball point pens you will
probably find what you need. You want to raise the ride height a bit without making it too stiff.

Hopefully this is all you will need to do. To get at the front damper you have to take apart the CD module. Theres lots more screws...(cont)

OSU4Runner

Wow.....you really dug into that thing..........my recommendation - buy an aftermarket cd player, you'll be glad you did.

ozziesironmanoffroad

yeah, just dont buy jensen, or the knockoff brand of jensen.

OSU4Runner

Jensen's are horrible x2 on that

ozziesironmanoffroad

yeah, i had to buy a jensen knockoff when my alpine shorted out. note to self: connect a ground to the stud and bolt on the back of the stereo. im thinkin this time when i buy one ill try a pioneer stereo i usually have good luck with pioneer stuff

tns1

(cont)
PIC4
PIC5
The CD module has been removed from the HU case. Keep all those screws and plates organized.

PIC6
The CD module with the bottom plates, circuit boards and front damper removed. The drive plate holds the disk motor and laser. You can see the CD thru a cutout in the drive plate. Just above the 'E-25059A' marking is where I trimmed a metal corner. If you don't feel the need to trim the metal, you can just fix the damper and reassemble (cont).

tns1

PIC7
You need to be part masochistic watchmaker to go further. Get your tweezers and dental probes ready...

This step involves removing the six small springs which WILL shoot across the room. Do yourself a favor and tie some monofilament to each spring before you try to remove it.

The CD module with the drive plate removed. To eject (or load) the CD, apply from 3v to 9v on the transport motor terminals. A 9V cell should work. Do this a few times and you will see the problem. Without no CD, the drive plate is trapped by two metal hooks on the case. Those hooks won't let go unless you load a CD, but the CD itself blocks removal of the drive plate. My solution was to take an old CD and cut it in two on a line about an inch from center. I loaded this at an angle and then rotated it so I could still remove the drive plate.

PIC8,9
A bit of prying and a few curses later and here is the drive plate. The two rear dampers here were fine. This is when I trimmed the metal corner with a dremel tool. I covered everything else to keep metal dust out. I also trimmed the front damper brace since it hits at the same spot. The front damper looks OK, but there must be a tiny hole that let out the clear oil. I used a small screwdriver to pack it with black wheel bearing grease. I reasoned that it was about the right consistency and would not melt or drip away, although I don't know if this is a long-term solution. You could possibly cut and insert some very soft air filled foam, silicone or latex, but I think the earplug foam would be far too stiff.

After the fix, I could shake the whole thing and not get any metal-to-metal contact. I have road tested this on some pretty good potholes and it seems to be 100% fixed.

Henrythewound

nice job, I think my player in my 2000 does that. I like the oem look but I would probably buy an aftermarket rather than do surgery on the OEM one. Where did you get the springs and how did you know what tension/gauge to get?

wormhole

Nice writeup.

My 4runner came with the factory 3 disc changer and a few days latter the thing ate one of my cd's. I had to pull the whole dang thing to get it back. Recommend getting an aftermarket one.

tns1

I found some springs in an assorted spring kit I had laying around. I don't remember where exactly I got this kit, but don't expect to find any at an auto parts store. You might try VCR parts places like MCM or better yet mcmaster.com (they kick a**). The springs are common coil style extension springs but pretty small and weak. I really think if you can get some old ball-point pens the spring inside will be near perfect. To get an idea of tension and length, all you need to do is bend a loop at one end and hook it on the drive plate mount alongside the old spring, and pull the other end until the CD raises up a bit. All you are trying to do is compensate for the weakness in the old springs. A small rubber band would even work if it would just last.

I don't think the springs alone will help if your damper is shot. Without damping that drive plate is going to bounce further and further until it hits something. All it takes are the right road conditions.

tns1

Over three years later and this fix is still working. I prefer the look of the OEM radio and I still occasionally use the tape player and CD, but I have put in an AUX input adaptor so I can just plug in an MP3 player.