I don't think I've ever encountered a thread here on the subject of "lifetime" or "no recommended service interval" on manual transmissions. I understand that automatics all still require service, but it appears that requirements for manual transmissions are fading away. We used to have cars with drain, level, and add openings. Then we had one that just had a dipstick (yes in a manual) and nothing else. The '04 SAAB we're driving now has the holes, but no service interval, and actually requires that the front suspension be dropped to accomplish a drain / refill. At 120K (we bought the car with 20K) I got nervous and had the oil replaced anyhow. They said it was somewhat discolored but didn't smell burnt, and there was no sediment or metal particles adhering to the drain plug. So should I have worried in the first place?
Views on no-change MT oil?
- Thread starter Rico567
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a lot of companies have lifetime fills on their automatic transmissions
I agree with Hyundai when it comes to their automatic transmissions 30,000 is the number
I agree with Hyundai when it comes to their automatic transmissions 30,000 is the number
The oil is not likely to "smell burnt" in an MT.
I think the biggest reason to change the oil in an MT is the threat of non-ferrous particles (not caught by the magnet) causing increased bearing wear. Gears won't care but rolling element bearings will not be happy.
In addition the magnet may be loaded up with ferrous particles meaning the remainder are still floating around.
Same with the diff or final drive, most of the metallic debris will wear off during the first few thousand miles/kms, making the first change the most important.
I think the biggest reason to change the oil in an MT is the threat of non-ferrous particles (not caught by the magnet) causing increased bearing wear. Gears won't care but rolling element bearings will not be happy.
In addition the magnet may be loaded up with ferrous particles meaning the remainder are still floating around.
Same with the diff or final drive, most of the metallic debris will wear off during the first few thousand miles/kms, making the first change the most important.
Oxidation? Shearing? Though I would think the EP/EW additives in most gear oils would help prevent that. I would additionally think there is much less moving parts in a manual so gear oil would wear at a far lesser rate than fluid in an AT.
Most people see an improvement in shift feel when changing their MTF, though I'd attribute that to difference in friction modifiers and viscosity between the factory fluid (if it is still such), which may have sheared by the time the change happened, not necessarily changing with factory fluid or aftermarket.
Most people see an improvement in shift feel when changing their MTF, though I'd attribute that to difference in friction modifiers and viscosity between the factory fluid (if it is still such), which may have sheared by the time the change happened, not necessarily changing with factory fluid or aftermarket.
I would have changed it. I'm going to change the "lifetime" MT fluid in my Cruze soon.
Gear oil is very long lived. I've run industrial gear boxes for years with a gear oil change only if the oil appeared to be bad from heat (near the boilers) or from water intrusion. Even when the oil looked bad, the gears and bearings looked fine.
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