Diff lock confusion...

[farmerboy]

Hi all, I have read lots but I am afraid I am still a bit confused regarding which oil to use for the diffs and transfer box on my 2003 d4d.
I believe that special diff oil is needed if I have a limited slip diff... how can I tell what type of diff I have?

I have a rotary type switch which engages a diff lock but I do not know if this is for the transfer box or the front diff or the rear diff? Sorry to be so dim but I want to be confident that I use the correct oil when I change the diff oils.


Also, it says in my handbook that the auto box fluid does not need changing (unless it needs changing?) I am a little bemused by this and after 126,000 miles surely some fresh transmission fluid is a good idea.... I will be towing quite heavy loads (horses).

Thankyou in advance.

 

[Chris]

The rotary switch is for the rear diff. The centre diff doesn't have a switch. That's what HL is for on your second little gear lever. I presume you have an LC3?

 

[farmerboy]

Yes LC3... thanks. I guess that I do not have limited slip diffs then?

 

[Chris]

Well here's a clue, you wouldn't have a rotary switch for a limited slip diff would you

 

[farmerboy]

Thanks Chris, I was a bit confused because I have had 4wd vehicles in the past with a variety of "locking" and "viscous coupling" devices. My understanding is that the transfer box is locked via the small lever, the rear diff is locked via the switch on the dash and the front diff does not lock and is not of a limited slip design therefore standard spec diff oil is ok.

Thanks again.

 

[Chris]

There you go. In one.

 

[Andrew T]

The rotary switch is for the rear diff. The centre diff doesn't have a switch. That's what HL is for on your second little gear lever. I presume you have an LC3?

The centre diff does have a switch, it is on the centre console beside the heated seat switches, and the descent control switch. when engaged you will get a warning light on the instrument panel as it will switch off the vehicle stability control system too.

If you do not have rear diff lock, dont worry you probably have a LC4 or LC5 and they have traction control which is better than a single axle diff lock.

 

[Andrew T]

Hi all, I have read lots but I am afraid I am still a bit confused regarding which oil to use for the diffs and transfer box on my 2003 d4d.
I believe that special diff oil is needed if I have a limited slip diff... how can I tell what type of diff I have?

I have a rotary type switch which engages a diff lock but I do not know if this is for the transfer box or the front diff or the rear diff? Sorry to be so dim but I want to be confident that I use the correct oil when I change the diff oils.


Also, it says in my handbook that the auto box fluid does not need changing (unless it needs changing?) I am a little bemused by this and after 126,000 miles surely some fresh transmission fluid is a good idea.... I will be towing quite heavy loads (horses).

Thankyou in advance.

Regarding gearbox oil... I am told by my Toyota garage that whilst at each service the gearbox oil is examined, if you use Toyota dealerships, essentially it was designed to be a sealed for life unit. However I am like you and would like to change out the oil and filter around the 100k mark.

I am also told it is the same box in the 100 series.

 

[farmerboy]

Sorry to say I do not have any of those wonderful switches! (just the diff lock rotary switch) It is an LC3.... not sure if I have stability control.

Is an auto box oil change simply a matter of undoing the bung and re-filling or does it need to be pumped / flushed through?

 

[Chris]

On a 2003 LC3 Andrew, really? Mine certainly didn't not did it have hDC

 

[silvercruiser]

Sorry to say I do not have any of those wonderful switches! (just the diff lock rotary switch) It is an LC3.... not sure if I have stability control.

Is an auto box oil change simply a matter of undoing the bung and re-filling or does it need to be pumped / flushed through?

im not sure on the procedure, i would check what oil goes in the auto box and see how much it is. I think Crispin on here enquired before, and it was a small fortune.

 

[fast but dim]

If you're really stuck you could always run the car over to http://westcoastoffroad.co.uk/ near southport. They'll change all your fluids, and show you what everything does!

Every other year I get them to drop the diff, gear and transfer box oils. I could do It myself, but you're 100% certain the right oil is going in the right place. Very reasonable rates, and you only get charged per litre used.

 

[farmerboy]

Many thanks for the link - I shall check them out.

 

[fast but dim]

Many thanks for the link - I shall check them out.

They're superb, LC specialists and enthusiasts, great lads, and not too far from you in SH! They have a garage and a shop stocking all sorts.

I use them for Mot's, and get them to look the lc over to pre empt any issues. 100% trustworthy.