W124 - More focus on the mild vibrations on the steering and how the surgery became a larger operation

Its lockdown again - MCO 3.0.

A lot of work has been done and a number of parts were replaced to get the car to where it is today. I am still not quite at peace with it at this moment for some of the smaller issues. But of course, it has transformed from the time that I brought Rhino home about 8 months ago.

I did some reading and also asked on forums what could be causing my vibration issues but have not got concrete replies. Also while a number of parts were previously been replaced, it seems that they were fitted with low-quality version, let alone not made in Germany.

This time around, I am focusing on the vibrations and was curious to know what causes vibrations in a car, despite those that I have addressed. Both the links below are a good start that points out possible issues:

The common theme for vibrations starts with the wheel, the wheel must be aligned, balanced and check the camber and caster adjustment where possible. In my case, I have done all of this.

Next, are bearings, while the regular inspections show that the bearing is not showing any signs of damage, I do not have a record of when was the last time it was replaced, and hence I am getting them replaced.

As for the absorbers, they have been completely replaced all-around with due mounts renewed as well.

The Tie rod was replaced recently and as I look into some of the work that has been done, I noticed some weird repairs that were carried out, the tie rod in the past was only replaced on one end, the lower arm balljoint was also replaced on one end. I am a believer that if a component comes in a pair, they both should be replaced at the same time and not one at a time.

While my engine mounts and gearbox mount has been replaced, I am unsure of the quality and will want to have them checked, from the recent replacement that was done, mostly on parts that are about 8 months old, low-quality parts just don't cut it, despite spending on the replacement brand new parts, they do not last.

A good giveaway is the charges that are invoiced on the parts. If parts are sourced by garages, they normally would mark up the price by anything above 20% to 60% normally, and if the parts upon markup are not too expensive, it's a good sign that the parts are cheap and may not last long. This was a lesson that I learned on this journey.

As I now get my parts from a genuine part stockist, I get to compare the parts price against what I was charged and from there, I saw a few items that fall into this list of not being in a good quality-price range.

So this time around, I am replacing the following parts:

Engine mountings - Lemforder
Gearbox mounting - Lemforder
Wheel bearings, front and rear - FAG
Lower control arm bushes - Lemforder
Lower control arm balljoint - Lemforder
Front torsion bar bushes - Lemforder and Mercedes original
Absorber mounts, front - Lemforder
Rear subframe bushes - Lemforder
Rear-wheel arms, 5 arms a side - Lemforders
Rear torsion bar bushes - Lemforder
Rear spring pads - Mercedes original

The following items were not replaced as they were replaced 6 months ago:

Axle bushes - Lemforder
Axle mounts - Lemforder
Rear knuckle ball joint - Lemforder

All the replacement parts were purchased from the parts stockist. The Torsion bar bushes will need to be compared against the one that was fitted to ensure a correct part is procured.

This is a job that would take the mechanic a couple of days and I am fine with that as I do not believe in pushing them to have a job done quickly. And since it is the lockdown, the mechanic can take his time working on the car.

It is the eve of the lockdown and the good ol' mechanic asked if I can send the car in. The wait is now for the mechanic to start his surgery and hopefully come close to resolving the vibration issue.

Update #2:

When the mechanic was working on the rear wheel bearing, I asked how were the arms and bushing. His reply to me was that the bearings have never been replaced and the arms and bushes are mostly original from the factory, making them 26 years old. I asked that would it be good for us to change them now since some of the parts are already removed and he said yes

So upon getting a list of parts, I told the mechanic to proceed while I get him all the parts needed.

He went out to press the rear bearings to place and updated me that the right-hand side bearing was already humming. When he started working further, the rear spring pads were overdue for replacement. In his words, the spring pads are destroyed. I wasn't surprised as we have had parts on this car that have never been replaced.

Update #3:

I was updated that the arms were removed and replaced, the work to be completed soon. The subframe bushes were hardened and are only half of the initial height and all rubber on the arms were hardened.

Update #4:

The mechanic sent me a quick video of all the work that has been done. The rear arms and bushing has been completely replaced, the long shaft flex disc and coupling, bearing, and mount have been replaced and the whole front arms, bushes, mounts, and rods were replaced.

In his finding, the front engine mount which was only 7 months old has compressed by about 1/3 of the new ones. The old engine mounts were allowing the engine to be rocked with bare hands. The old transmission mount has a low-quality build, which is 7 months old, absorber mounts look worn.

The front wheel bearing that initially was not suspected to be faulty but was replaced when I asked for one was found to have disintegrated upon removal, again a part that has never been replaced.

The car was then taken to the wheel shop for balancing, alignment, and caster/camber adjustment. The mechanic says the car drives a lot better now. I had another which was the jerk from the 1st to the 2nd gear, apparently, the mechanic also updated that the jerk has reduced and feels like a normal car. He further said that he can feel the bushes and arms are all working on uneven roads giving the car good handling and road grip. In the past, there were some squeaks, the vibration of the steering wheel, and the overall comfort level of the car was not optimum. I will not be able to confirm until I drive it personally, hopefully soon

Looking forward to driving it again, but since it is the lockdown, we have sent the car for some rust repair and panel alignment that was found. I really hope that the car gets better when I get it back again. Looking forward to it.

Update #5:

The car was collected by a friend, Mr. Tarwin, on my behalf and took it for a drive. Despite the balancing, alignment, camber/caster adjustment completed, the car did not drive well as it still had some rear vibration, albeit mild.

He took it to another wheel shop to have a full assessment and inspection. This shop uses a manual system instead of an electronic one. The tire guy quickly pointed out that the front right alignment, rear alignment were out of spec. He also adjusted the camber and caster accordingly. Once all that was done, he did the on-wheel balancing for all the wheels.

As a result, the car almost transformed with the exception that there is a mild vibration that is originating from the rear. Tarwin will drive the car more and if needed return to the tire shop for a further fine-tune for the rear.

Update #6:

After visiting the wheel shop the last time as per the previous update, the drive was still not up to par. Upon checking the wheel balancing on the rear right needed to be corrected. Also, the front caster adjustment was not correct and was aligned back. There was also vibration caused by braking is not sorted out. A check on the brake at the mechanic revealed the rear left discs has had some abnormal wear on it which I believe was caused by the jammed caliper before the service was done before. A new set of discs were replaced. The engine fan clutch was also checked as it was making some noise, so while replacing that, a replacement fan bracket (with bearing) was also replaced. The clutch was worn out as after the replacement, the engine feels lighter. The noise has yet to be fixed and that will be documented in the next episode.

Hot tip:

If a part needs replacement, replace them in a pair unless not possible. Parts are made with similar service life, if one fails, the other will fail soon too, save on labor by doing it in a pair.
Opt for parts with a good brand, not just any brand that the mechanic says good.
Build a relationship with a parts stockist, someone who you trust and along the way get preferential pricing.
If a workshop insists that they will want to buy the parts, watch the cost, you are already paying them for labour, so don't feel bad about bringing in your parts if they accept. Else, maybe look around for another workshop that can work with you and your parts, remember, you can save quite a bit here.
Always have a financial buffer when you are planning for work, chances are, it would cost a little more upfront especially when some work is not planned, but it will be cheaper and satisfying in the longer run. Some repairs are not obvious until parts are removed.
Build a list of all parts that were replaced, by when whom, mileage and cost, the next time a part needs replacement, look at the list if something is amiss. If it is, reconsider your trajectory with the stockist/workshop accordingly.

Pictures: