BHPian bamaboy recently shared this with other enthusiasts:DIY: Detailing My Mercedes-Benz GL 350dDuring February 2023, I took up detailing the GL myself. I’ve been doing basic DIY detailing since 2012 using tried and tested products like Klasse AIO, Klasse High Gloss Sealant Glaze and the ever-reliable Collinite 845, all applied by elbow grease. Collinite 845 in particular has been my go-to sealant wax for over 12 years. It always delivers outstanding results. Before handing the car over to a professional detailer I wanted to try my hand at using a machine polisher. I reached out to an old friend and fellow BHPian SunnyBoi for advice. On his recommendation I picked up a North Wolf 5 inch DA Polisher which is a clone of the Rupes Bigfoot Random Orbital Polisher along with 5 inch yellow polishing pad and a black finishing pad. I also got Meguiar’s Ultimate Compound. The GL had significant oxidation and plenty of swirl marks. I wanted to preserve the factory paint as much as possible so I chose a mild abrasive polish for my first machine detailing attempt. After a thorough wash and surface prep we started polishing with the yellow pad and Meguiar’s Ultimate Compound then finished with Collinite 845 applied using the black finishing pad. The results were far better than expected. The paint came alive with a deep gloss and much improved clarity. We also applied Ceriglass Pro, a cerium oxide-based windshield polishing compound, to remove hard water stains and restore factory like shine and visibilty. Additionally, we applied Turtle Wax Trim Restorer on the faded black plastic trims and the lower section of the bumper grille. These small touches made a noticeable difference in the overall appearance, bringing back the contrast and freshness to the aged surfaces. My driver assisted me through the detailing process and was just as thrilled with the outcome. The shine at the end of it all was deeply satisfying and made all the hard work feel worth it. MaintenanceBy March 2023, I had completed six months of ownership of the GL and had clocked nearly 6,000 km since the car left Lucknow. It was time for routine – B service. The previous major service, including the last oil change, had been carried out in September 2021 at the 53,500 km mark. How did I know? Well, the car came with an unexpected easter egg – a handwritten logbook maintained by the first owner’s team. Every odometer reading for each major outing including service visits was recorded right from day one. It provided a rare and clear picture of the car’s complete service history. Although the car wasn’t used much after 2017 and spent most of its time parked in a garage, it was revived with a major service in September 2021. Here’s a list of work done at Viraat’s Automotive Garage : Service Post For the service, I ordered the following: Engine Oil – 9 litres of Mobil 1 ESP 5W30, which meets MB 229.51 Low SPAsh specification. Oil Filter – Mahle Air Filters – OEM AC Cabin Filter – OEM Coolant/Antifreeze – 2 litres of Mannol 4113 AG13, which meets MB 325.0 specification. I sourced the engine oil and coolant from Amazon, while the filters were ordered through Viraat. Once we opened the engine cover, my love-hate relationship with the OM642 truly began : There was clear evidence of oil seepage around the turbo intake area. The sight of an oil-soaked intake wasn’t exactly reassuring. I did some research, checked in with Viraat and found that the Intake seals had worn out and were due for replacement. It’s a textbook issue with this engine. The culprit is the failed intake manifold seals, a well-documented weak point in the early OM642 design. Over time, the rubber gaskets harden and shrink due to repeated heat cycles, allowing oil mist from the crankcase ventilation system to escape and collect around the turbo inlet and intake runners. This isn’t a unique problem to my car. It’s a known design flaw in the earlier generation of OM642 engines. Mercedes eventually addressed it in later versions like the W166 and X166 by revising the intake manifold and improving the sealing system. Unfortunately, the X164 GL still uses the older layout, which is prone to these leaks as components age. YouTube also turned out to be a goldmine with plenty of videos and DIYs showing similar cases with the OM642. Here’s a helpful video that walked me through the fix:https://www.youtube.com/watch?v=D9AL…nnel=DrewFixIt Viraat immediately dispatched the new intake seals, and while we waited for them to arrive, I decided to take things a step further. I planned to include EGR valve cleaning, throttle body cleaning, and intake manifold cleaning, since these areas hadn’t been addressed during the previous service. The PCV valve also arrived about a month later, and I had it replaced. With the service complete, here’s a breakdown of the costs incurred: Air Filters (pair) – Rs.3200 Oil Filter – Rs.850 AC Cabin Filter (set of 2 elements) – Rs.2200 Intake Seals – Rs.2800 Engine Oil (9L) – Rs.10500 PCV Valve – Rs.3800 Coolant – Rs.4500 Miscellaneous – Rs.1000 Labour Charges – Rs.8000 Total: Rs.36850/- What began as a routine Type B service with standard fluids and filters gradually turned into a more thorough preventive maintenance session. Given the OM642’s tendency to accumulate carbon deposits in the intake tract particularly around the EGR and swirl flap regions. It made sense to get everything cleaned and refreshed in one go. I also ordered another spare set of Intake Gasket set to kept as spare for future. With the intake manifold cleaned, a new PCV valve installed, and fresh engine oil and filters in place, throttle response noticeably improved. The engine felt more eager and responsive, offering better drivability and a slight uptick in acceleration. From that point on, the GL ran effortlessly smooth. Ownership ExperienceI got the GL in September 2022. The car was originally registered on 18 August 2010, with a manufacturing date of April 2010. Its RC was valid till 2025 under Haryana RTO. However, being a diesel vehicle over 10 years old, it was no longer permitted to run in Delhi and NCR due to NGT regulations. We began the NOC process in December 2022. Since the car had an older, certificate-style registration document, the first step was to issue a new smart card and update the records on the Vahan portal. Another hurdle came up due to the car bearing a VIP registration number. The number had to be surrendered, as such VIP numbers are retained by the RTO and later auctioned. Because of this, the car was re-assigned a new HR registration number from the HR70 series. This made the transfer process unusually tedious and time-consuming. Finally, in August 2023, the registration was updated and the NOC was issued, allowing us to transfer the vehicle to Chhattisgarh RTO. Registration plates were now changed bearing new number. In January 2024, due to a moment of carelessness, my driver damaged the rear left tyre by scraping it against a boulder. The sidewall was torn, rendering the tyre completely unusable. Since the Continental tyres on the car were manufactured in 2021 and already three years old, I wasn’t eligible for an unconditional warranty replacement. I ordered the same Continental CSC5 SUV tyre in 275/55 R19 111W spec from Tyremarket and got it installed, balanced, and aligned. Total damage to the wallet – Rs.22,000. In February 2024, we embarked on a family road trip to Khajuraho, Chhatarpur, and Maihar – a 1200 km round journey that turned out to be one of the most memorable. The GL performed flawlessly throughout. Touring in this car is supremely comfortable, and it shines on long-distance highway drives. Our route from Bilaspur to Katni took us through Shahdol and Anuppur. This stretch in Madhya Pradesh included a lot of single lane sections with rough patches, especially near Anuppur. The road conditions improved after Katni. This journey gave me a deeper appreciation for the GL’s suspension system. For those unfamiliar, the AIRMATIC system uses pressurized air bellows in place of conventional steel springs. Each strut houses an air spring which is inflated or deflated in real time by an onboard air compressor connected to a reservoir tank. This setup allows the system to adjust ride height and damping characteristics on the fly based on driving conditions and terrain. Another clever feature of the AIRMATIC system is its automatic speed-sensitive lowering. Once the vehicle crosses around 80 kmph, the suspension gradually lowers itself to its minimum ride height. This helps reduce aerodynamic drag, improves high-speed stability, and lowers the center of gravity for a more planted feel on expressways. The GL offers three suspension modes – Comfort, Normal, and Sport. The default is Normal mode, which strikes an ideal balance between ride quality and control. Comfort mode softens the suspension significantly, ideal for slow speeds and uneven terrain, but at times it can feel floaty and unsettled due to the softer damping. The system frequently adjusts air pressure in this setting to maintain ride comfort. Sport mode, on the other hand, stiffens the suspension noticeably. This mode is better suited for high-speed expressway driving or tight handling conditions, but in a tall SUV like the GL, it may feel unnecessarily firm. I find Sport mode more appropriate for sedans like the S-Class or EQS, both of which come with the ADS+ active damping system. My EQS handles Sport mode beautifully, but in the GL, it feels out of place for most real world conditions. In my experience, the Normal suspension mode is the sweet spot. It offers just the right amount of spring tension and damping to absorb bad roads gracefully while keeping the body stable. Over 60 kmph, the system really comes into its own. The ride remains flat and controlled even on rough surfaces. The GL seems to glide over road imperfections, making it a supremely comfortable long-distance cruiser. Paired with the torquey OM642 V6 Diesel and a gearbox engineered for relaxed highway cruising, the GL becomes an exceptional long-distance tourer. It effortlessly absorbs road imperfections and remains composed even on patchy stretches. The AIRMATIC system works silently in the background, delivering a flat and sublime ride. At cruising speeds over 60 kmph, the suspension really comes into its own and makes covering miles a genuine pleasure. Except for the tyre damage, the GL ran fuss-free for a full year without any additional expenses. By March 2024, the odometer had touched the 66,000 km mark, which meant I had covered nearly 11,000 km since taking ownership. It has been immensely rewarding for the sheer comfort, commanding road presence and undeniable snob value it brings every time I take it out. The GL quickly became my go-to daily runner, thanks to its practicality and effortless drive. Naturally, the W205 and W124 E-Class saw much less use. The 2023 Tucson, on the other hand, was mostly reserved for outstation business trips, where its efficiency made it the sensible choice.Check out BHPian comments for more insights and information.
