Screwdriver
Active Member
- Joined
- Oct 20, 2008
- Messages
- 420
Spent alot of time researching fluids for my W115/ W123 over the past decade, so thought I'd share here with links for anyone interested in preventative maintenance for their Classic(s):
1) Engine Oil: This one has been discussed to death but I will share that I find that Liqui Moly's 15w40 MOS2 engine oil suits my Classics better. More specifically, idle noise is lower and low speed acceleration is smoother.
2) Manual Transmission fluid: Mercedes continues to insist on Automatic Transmission fluid Type A Suffix A. This is very hard to find in smaller quantities. Fortunately, Lube Finder sells 1L Shell Spirax bottles (2 Litres needed). I use Liqui Moly's MOS2 gear oil additive for notably smoother shifts (40 g needed).
3) Power Steering fluid: Interestingly, Mercedes has historically recommended ATF for the power steering fluid pre 90's but switched to specialized PS fluid in the W124. I believe Kent Bergsma's hypothesis is accurate in that PS fluid is likely more protective than standard ATF. I went with the Febi non-synthetic fluid on my cars
4) Rear Differential fluid: Mercedes rear diffs need a Hypoid GL5 75W90 fluid. I went with a fully synthetic Liqui Moly fluid.
5) Additives: I've had incredible results using these 4 additives only and have found most others to underachieve if at all. A quick search will show you I'm not the only one to have noticed these results and it's important to use them as instructed
AUTO-RX: When added to all 4 of the above fluids, using the exact application instructions over the past 15 years, I've measured increases in compression, elimination of blowby and fluid leaks, alongwith the associated benefits that come along from these improvements. 2X bottles in the motor oil.
CHEVRON TECHRON: Available for petrol or diesel, this American additive is the only tank added product that delivers noticeable improvements regardless of fuel type. I use one bottle every year before the winter.
SEAFOAM (Petrol only): When sprayed lightly through the intake manifold and allowed to soak on the pistons, this product drastically reduced carbon buildup in the combustion chamber on my vehicles, and improved throttle response substantially. I don't recommend adding this in the tank for diesel vehicles because of the potential for damaging perishable fuel pump components, based on mixed feedback.
DIESEL PURGE (Diesel only): When I ran two bottles as part of a closed loop system in my diesel vehicles, I've noticed substantial increases in smoothness, throttle response, economy and reduction in exhaust smoke. This works especially well if your fuel system has been neglected.
Hope these help (and that this thread doesn't spark another oil debate!)
1) Engine Oil: This one has been discussed to death but I will share that I find that Liqui Moly's 15w40 MOS2 engine oil suits my Classics better. More specifically, idle noise is lower and low speed acceleration is smoother.
2) Manual Transmission fluid: Mercedes continues to insist on Automatic Transmission fluid Type A Suffix A. This is very hard to find in smaller quantities. Fortunately, Lube Finder sells 1L Shell Spirax bottles (2 Litres needed). I use Liqui Moly's MOS2 gear oil additive for notably smoother shifts (40 g needed).
3) Power Steering fluid: Interestingly, Mercedes has historically recommended ATF for the power steering fluid pre 90's but switched to specialized PS fluid in the W124. I believe Kent Bergsma's hypothesis is accurate in that PS fluid is likely more protective than standard ATF. I went with the Febi non-synthetic fluid on my cars
4) Rear Differential fluid: Mercedes rear diffs need a Hypoid GL5 75W90 fluid. I went with a fully synthetic Liqui Moly fluid.
5) Additives: I've had incredible results using these 4 additives only and have found most others to underachieve if at all. A quick search will show you I'm not the only one to have noticed these results and it's important to use them as instructed
AUTO-RX: When added to all 4 of the above fluids, using the exact application instructions over the past 15 years, I've measured increases in compression, elimination of blowby and fluid leaks, alongwith the associated benefits that come along from these improvements. 2X bottles in the motor oil.
CHEVRON TECHRON: Available for petrol or diesel, this American additive is the only tank added product that delivers noticeable improvements regardless of fuel type. I use one bottle every year before the winter.
SEAFOAM (Petrol only): When sprayed lightly through the intake manifold and allowed to soak on the pistons, this product drastically reduced carbon buildup in the combustion chamber on my vehicles, and improved throttle response substantially. I don't recommend adding this in the tank for diesel vehicles because of the potential for damaging perishable fuel pump components, based on mixed feedback.
DIESEL PURGE (Diesel only): When I ran two bottles as part of a closed loop system in my diesel vehicles, I've noticed substantial increases in smoothness, throttle response, economy and reduction in exhaust smoke. This works especially well if your fuel system has been neglected.
Hope these help (and that this thread doesn't spark another oil debate!)
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