Transmission oil change intervals

Beano

Beano

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Fellow Frogger
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Your opinions requested, please gentlemen :

Please correct me if I am wrong, but I have always thought that as a general rule, transmissioin oil is changed at 20,000 Km intervals.

Is there any point in changing it at shorter intervals ? It often looks ratherr dirty then.

For instance, if you were to own a car which has no transmission sump plug, would you take the sump and have one welded in (easy enough to do, as I have an old 505 auto trans sump), so that every 20,000 Ks you would change oil and filter, but half-way through that you could renew the oil, without doing the filter ?
That would certainly be easy, without having to take off the sump.

Or am I getting too obsessive ?

I know that certain makes of car have "sealed for life" transmissions, but I have always thought that to be a dumb idea, as I have heard that their life is not really that long.
 
My vote.
Obsessive.
How many km's do you drive?
Can't get up any real mileage up at 15 km/hr in Melbourne traffic.
When selling car put in brake fluid to swell seals and stop leaks :crazy:
 
Hey Beano,
Don't go and read the comments about CVT fluid changes in another post on this forum then.
Other peoples logic may possibly upset you.
 
Oh, I'm used to other peoples' logic being at odds with mine.

I'll do a search.
 
My last two Volvos have had “sealed for life” transmissions. I choose to change the relatively expensive fluid every 40 -50k. First car was still going fine at 225k, the current one due now at 150k, but still fine. Seems like relatively cheap insurance. They may be sealed for life, but really this just means it will most likely get through the warranty period.
 
alan moore said:
My last two Volvos have had “sealed for life” transmissions. I choose to change the relatively expensive fluid every 40 -50k. First car was still going fine at 225k, the current one due now at 150k, but still fine. Seems like relatively cheap insurance. They may be sealed for life, but really this just means it will most likely get through the warranty period.
Click to expand...

I have taken a similar approach with my Laguna which supposedly has "sealed for life" transmission. I had the fluid changed at around 100,000k.

Ian.
 
Hardly obsessive, Ian. Beano is talking about drilling a new drain hole, & switching to a 10,000km change interval!
 
Armidillo said:
Hardly obsessive, Ian. Beano is talking about drilling a new drain hole, & switching to a 10,000km change interval!
Click to expand...

I just paid someone (an autotrans specialist) to take the sump off and drain and refill with correct fluid. I'm not about to start drilling holes in the sump!

Ian.
 
I am pretty sure that the 4HP20 (as fitted to my XM) was advertised as only requiring a level check, & possibly a top up, at infrequent intervals (50,000km?).

May have had something to do with the need for a tranny rebuild at 100,000km!

Mike (previous owner) & I have tried a more frequent interval, but alas it thumps on down changes - possibly damage was done in the 40,000 km between rebuild & Mike's purchase.

Mike purchased 60 litres of expensive tranny fluid, most of which he passed on to me! How's that for obsessive!

Cheers
Alec
 
Hi Beano :)
There is another way to do an oil change without removing the sump etc. You can buy a cheap oil pump with a small tube which you can put down the dip stick tube or even down the fill hole probably depending on the tranny.
I have done that before to achieve what you want. Easy enough.
Jaahn
 
Hardly obsessive , frequent oil changes do extend the life of an auto ,
I purchased a cheap $35 vacume oil extractor from Ebay a few years ago , tube goes down dip stick hole and sucks the oil out , only takes a few minutes and you dont even need to jack up the car . You need to repeat this a few times as you can not get the oil in the convertor to drain .
Since then I have changed autos oil on all three of my cars to a full synthic Penrite , all three had a noticeable improvement , smoother up shift and cured a shudder on down shift in the Mitsubishi .

 
Beano said:
Your opinions requested, please gentlemen :

Please correct me if I am wrong, but I have always thought that as a general rule, transmissioin oil is changed at 20,000 Km intervals.

Is there any point in changing it at shorter intervals ? It often looks ratherr dirty then.

For instance, if you were to own a car which has no transmission sump plug, would you take the sump and have one welded in (easy enough to do, as I have an old 505 auto trans sump), so that every 20,000 Ks you would change oil and filter, but half-way through
Click to expand...

Or take the cheap and nasty solution used on many BW35 in 504s - make a hole in the tranny sump with a punch and use a rubber plug as a sump plug. :nownow:
 
504 with BW 35 without drain plug.
Remove one of the oil cooler pipes from radiator, start engine allow oil to run into a container, preferably one with level marks. Stop engine when fluid ceases running. Refill with measured amount drained. Repeat if oil is discoloured/smelly.

Off topic. Now that I've entered into Non Froggy ownership ]2005 Toyo Corolla] Dealer service advises of the not necessary to change auto trans oil ?
Anyone...
 
Last edited:
Hmm, this rings a bell, but I can't remember why.
 
Armidillo said:
I am pretty sure that the 4HP20 (as fitted to my XM) was advertised as only requiring a level check, & possibly a top up, at infrequent intervals (50,000km?).

May have had something to do with the need for a tranny rebuild at 100,000km!
Click to expand...

^ This is what worries me.

The thing is : I have to take off the sump anyway, in order to drain the old oil. So why not get a plug welded in there ?
At the very least, I will be able to do a complete oil change more easily, by draining, refilling, doing a few Ks and then repeating the process..

I guess it's six of one and half a dozen of the other, as to whether to do that or suck it out through the dipstick tube.
 
I vote to have a drain plug welded in and do the oil change at whatever interval.
 
It is often forgotten that oil does not wear out. It can become contaminated with solids or liquids, it can be burned, but it does not wear out. A gearbox is a nice clean place to lubricate, and it stays clean for a long time unless you are in the habit of crunching gears on a regular basis, in which event an oil change will only be required at the same time it requires a rebuild.............
 
Although auto transmission fluid, like engine oil, has additives. Wouldn't these "wear out"?
 
Wildebeest said:
504 with BW 35 without drain plug.
Remove one of the oil cooler pipes from radiator, start engine allow oil to run into a container, preferably one with level marks. Stop engine when fluid ceases running. Refill with measured amount drained. Repeat if oil is discoloured/smelly.

Off topic. Now that I've entered into Non Froggy ownership [Toyo Corolla] Dealer service advises of the not necessary to change auto trans oil ?
Anyone...
Click to expand...


Ha! What Corolla?

I bought one too for my wife. 2005 wagon auto. Economic write off, 900 bucks. Good strong engine (country car driven by a lady who had it serviced professionally its entire life). Replaced the tailgate and rear bumper, put in power windows for the whole car, back on the road (all up 900 bucks in parts shipped across the country, did the work myself). New Bridgestone Re003, another 600 bucks or so for five. Didn't change the engine oil for two years because there were no leaks, no signs of use, nada (I did put in fresh oil when I bought it). Changed it recently when I had the pressure light come on under hard braking. There was still one liter of oil left in the engine, the car didn't seem to care so why should I? Not sure where it went, I suppose it was burnt in spite of showing no signs. It sure doesn't leak anything. Tranny oil (changed when I got the car as well) still looks fresh and up to correct level, so no worries. Car has 300k on the clock, so no biggie if it bites the dust. Other than that, no maintenance for two years, I call that awesome.
 
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