Outer Limits 4x4 Board

Hi,

Each time I check my gearbox and transfere case oil levels there different. That is the oil seems to travel betrween them. Same quantity of oil but sometimes it's higher in the Gearbox and sometimes higher in the transfere case.

The reason would have to be because I'm useing Shell synthetic 90 grade gear oil in both and it has about the same viscosity as water when cold and I'm sure its thinner when hot.

I think the seals between the two are ok as it was never a problem with the thicker mineral ep90 gear oil.

I'm thinking to install a high pressure and high temprature hose of about 12mm bore between the two filler plugs to try to keep the levels more constant. I haven't as yet checked the height of both filler plugs however for the purpose of this post we can assume they are at the same level.

Any Idea's

Assuming both plugs are the same level, it should work. Only problem may come if a bearing or something starts to die. You may end up with metal through both boxes instead of one. But magnetic drain plugs should fix that.

Leon, if you join the two fillers be very careful on steep left hand slopes as the oil from the gearbox could end up mostly in the transfer case- or vise versa for right hand slopes.....

ok theres an obvious fix for this problem.. use thicker oil! if u r interested, i'll suggest u product that i use. its great. really smooth operation an u can use it anywhere. i use it in my engine, tranny, both diffs, an my transfer case. never a problem.

Hi SimplyPV,

Okay could you tell me what the product is please. I'm interested.


David, I dont think it would be to big a problem with the oil draining one to the other as the connecting line would be sized to prevent this. But on the other hand you do raise an interesting point.

alright leon... i'll have to get back to u on taht tomorrow.. gotta dig up a bottle of it somewhere an give u the name brand. if u dont have it there.. i'll even buy some an send em over if ur willin to rembuse me.. trust me man, this stuff is great, so thick. so smooth... its a wonder

You may want to be careful with thicker gearbox oil too Leon, I had to change mine to thinner oil as I was having problems with grating in the cold weather. If your gearbox is getting old you too may find the same thing.

guys... its not standard oil..... its like glue... it stays on ur gears..... its great. trust me.. lemmie give u guys the name brand tomorrow an u can look it up if possible. if not, i'll post the label for everyone.

I think the gearbox-transfere connecting tube idea is open to experementation in as much as how do you run it.

Say with the middle of the tube about 25 to 50mm higher than the fill points ( this could keep the oil in the box-case closer to normal on steep terrain ) or maybe lower to help the oil transfer from box-case.

The reason I run the synthetic gear 90 is the transmission is in theory should run cooler, less wear, better gear changing and maybe a little better fuel economy. Same reason I run synthetic blend in the motor.

I run Shell semi synthetic blend and not full synthetic because Roza has just clocked over 260000 Klm's. She uses about 1 litre of full synthetic in the engine over 5000 klms and not much semi synthetic over the same distance. Sheel Helix Plus in winter and Shell Helix Sports 50 in Summer.