1970 142 gearbox oil

[Dc871f]

What oil should be used in the gearbox and differential?

Thanks.

[c1800]

Hi, and welcome. There’s numerous posts on this topic. Searching the forum will provide some info, both the 140 series and Amazon/1800. They used the same engine and differentials Best to check the owners manual too. I assume an M40 4 speed? Motor oil 30 W or 20w50. GL 4 Gear oil as well, not hypoid, 80-90 is fine for the transmission too.

For the differential HYPOID/GL5 gear oil approx 80-90 weight is what you need.

You might find it helpful to get your hands on a Haynes manual for the Volvo 140 series. Lot of info there.

Cheers

[Dc871f]

Originally Posted by c1800

Hi, and welcome. There’s numerous posts on this topic. Searching the forum will provide some info, both the 140 series and Amazon/1800. They used the same engine and differentials Best to check the owners manual too. I assume an M40 4 speed? Motor oil 30 W or 20w50. GL 4 Gear oil as well, not hypoid, 80-90 is fine for the transmission too.

For the differential HYPOID/GL5 gear oil approx 80-90 weight is what you need.

You might find it helpful to get your hands on a Haynes manual for the Volvo 140 series. Lot of info there.

Cheers

Thank you.

I have the Haynes manual, and the recommended Hypoy B for the differential when I search for it doesnt even come up anywhere, and searching for an equivalent results nothing as well. I imagine Hypoy and Hypoid are equivalents.

Its hard to even find a reference to what Hypoy B even is. There is a C on the market though, and I think its a Castrol product.

[142 Guy]

I suspect Hypoy may be a product name that was used by Castrol. As C1800 notes, GL5 gear oil is the product you want for the differential with the weight as specified in the owner's manual or the service manual.

I think I use Castrol Synthetic 75W90 GL5 in the diff on my 142 E. 80W90 is less common these days and is only easily available in 20 l pails where I live

GL 5 is meant for hypoid gears and has extreme pressure additives which are typically sulfur based. The sulfur based additives are corrosive to brass and will damage the synchronizer rings which is why you must never use a GL5 gear oil in your transmission.

[Dc871f]

Originally Posted by 142 Guy

I suspect Hypoy may be a product name that was used by Castrol. As C1800 notes, GL5 gear oil is the product you want for the differential with the weight as specified in the owner's manual or the service manual.

I think I use Castrol Synthetic 75W90 GL5 in the diff on my 142 E. 80W90 is less common these days and is only easily available in 20 l pails where I live

GL 5 is meant for hypoid gears and has extreme pressure additives which are typically sulfur based. The sulfur based additives are corrosive to brass and will damage the synchronizer rings which is why you must never use a GL5 gear oil in your transmission.

How about GL-5 with a Moly additive for the diff?

[Derek UK]

Moly does have its advocates but isn't needed. The oil companies know what they are doing with regards to additives for the various applications. Whatever hypoid you pick for your axle, use it for your steering box. Volvo list oil for the box one grade down from the axle but as the box is likely a little worn by now and possibly has a tired lower seal the small extra thickness is useful. It also means you only need one bottle in the cupboard for top-ups.
As said DO NOT use hypoid in the gearbox.

[Dc871f]

Originally Posted by Derek UK

Volvo list oil for the box one grade down from the axle but as the box is likely a little worn by now and possibly has a tired lower seal.

100% correct, box leaks like a sieve.
I have some GL-5 on the shelf with the Moly, so I probably use it for the axle and get Castrol 30wt for the gear box.

Thanks for the help.

[142 Guy]

That seems like a plan, particularly since what is on the shelf involves no extra cost. Just make sure that what is on the shelf has enough left in the bottle to cover a fill on the differential. You don't want to drain it and then find that the on the shelf bottle only gives you a half fill.