YRV 4WD System Help

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Hi, im a new member as i have recently purchased a Daihatsu YRV. I bought the car pretty cheap to use it to get me to work in bad conditions....mostly snow. Its got many problems that i am currently sorting out but one what keeps getting me confused is the 4WD system.

So, only a few days ago there was pretty deep snow here so i took the YRV to work. It got me there no troubles but on my way home i decided to see how good the car really was in snow. I took it up some steep hills, on most of them it was ok but i did eventually get stuck. The front wheels were spinning but the rears were just staying still.I took the car home and attempted to find out how the 4WD system is supposed to work on it. After a while i ended up buying a workshop manual as i couldn't find much online about it.

As i understand this car is like a freelander where the rear wheels only engage when the front wheels have lost traction using the ''Transfer Rear Drive Clutch'' or ''viscous coupling''. Looking at the workshop manual it shows between the rear differential and prop shaft. But it does not say if it uses the same oil thats in the differential or it uses its own oil and is a sealed unit like the Freelander ones? The reason i ask this is because when the car is cold, the 4wd seems to work but once its warmed up it stops working. I did also change the diff oil for new (cheap car lube 80w90) and im not sure if its made any difference?

Any help on this would be very much appreciated as its given snow here again soon and i want to go and play Smile

Hi, I am not familiar with

Hi, I am not familiar with the YRV 4WD system but it seems that if it is a viscous coupling (& looking on the net suggests you are right that it is) then normally a silicone type fluid should be used and the higher the temp the more viscous / stiffer it gets whereas with normal gear oil the reverse is true which corresponds with the symptoms you are experiencing. I do not know exactly what fluid should be used but Freelanders use 100,000Cst (centistokes) stuff and you can get refurb kits. I would think you need to get that coupling as clean as possible of any gear oil that may be in it. I'm not sure how best to do this but you may be able to find something on the net. You may also find that the quantity of fluid is fairly critical for best performance. I have a Toyota with a viscous fan coupling and many owners on forums have found incorrect (low) fluid levels have caused the fan not to spin fast enough thus causing potential overheating whilst too much causes on too often. My point is that low temps & low oil may also be the issue in your case. The viscous fan oil tends to be around 10,000Cst so not suitable for AWD coupling.

Hey! I'm not able to help you

Hey! I'm not able to help you at all, but may I ask where you bought the workshop manual? I am thinking of getting one for myself, because I recently bought a 2004 YRV 4Trak (4WD).