Amazon: Differential oil / fluid

[wowoguy]

I'm working on the theory that there are no stupid questions here.

As part of routine maintenance I'll be replacing the differential cover gasket on my 1968 Amazon 131. Which oil / fluid should I use to refill it? It has overdrive; does this make any difference?

Brookhouse states SPICER DIFF COVER GASKET. FITS ALL AMAZON & P1800 MODELS, but they have a foot note which advises (YOU MUST CHECK WHICH MAKE OF AXLE YOU HAVE FITTED). Is this a contradiction if it fits ALL Amazons?

Thanks.

[swedishandgerman]

I would recommend a high pressure gear oil in the rear axle, GL-5 (Hypoid) and I would be more concerned about the pressure rating (GL rating) rather than the viscosity.

GL rating is based on how much pressure is exerted between the gear teeth as the gears are under load.

With reference to viscosity, 80 was recommended, but I don't know whether multi-grade gear oils were available back then. I like the idea of 80/90 for good viscosity in a range of temperatures.

There were different gaskets available so I would speak to the people at Brookhouse to makes sure you're getting the correct one.

PS: You're right! There are no stupid questions on this forum!

[Dibble]

Originally Posted by wowoguy

I'm working on the theory that there are no stupid questions here.

As part of routine maintenance I'll be replacing the differential cover gasket on my 1968 Amazon 131. Which oil / fluid should I use to refill it? It has overdrive; does this make any difference?

Brookhouse states SPICER DIFF COVER GASKET. FITS ALL AMAZON & P1800 MODELS, but they have a foot note which advises (YOU MUST CHECK WHICH MAKE OF AXLE YOU HAVE FITTED). Is this a contradiction if it fits ALL Amazons?

Thanks.

EP90 Hypoid gear oil is stipulated. Orpie Oils doing a reasonable deal here. I have just changed my diff and used this oil. Also replaced the Spicer Diff cover gasket from Brookhouse. Speak to Simon who will advise. Excellent service once again from Simon.

[jpws]

I've used the Castrol EP90
Available here and elsewhere

[swedishandgerman]

Originally Posted by jpws

I've used the Castrol EP90
Available here and elsewhere

I hope you don't mind me saying, but that's only GL-4 (moderate pressure hypoid gearboxes) and I would recommend something suitable for the very high pressures exerted on the gears in the old diff back there, GL-5.

As above, the the multigrades that are around nowadays for high pressure gear oils mean a better temperature range when only single grades were around.

[classicswede]

The 68 will be a spicer but older models could be spicer or ENV hence saying to check. Very simple visual check spicer is a rear loaded diff and ENV is front loaded

[wowoguy]

Thanks very much classicswede, swedishandgerman, Clan, jpws and Dibble.

I appreciate your time, expertise and thoughts; all useful. Since posting this question I was fortunate enough to spend some of yesterday with Simon from Brookhouse at the Sywell meet with my car parked beside his. He explained the differential gasket will fit my car and that the high pressure between the cogs when under load must be taken into account and that modern lubricants are better than the originals.

You guys have extended the conversation, providing more detail, so I now know what I am looking for. Simon said if I can't get it locally he has it.

I will ignore the previous local advice that the "Halfords Classic 20 W 50 engine oil would be OK!" (No, I didn't get that advice from Halfords. They were professionally cautious).

Thanks a million.

[Clan]

Originally Posted by wowoguy

I'm working on the theory that there are no stupid questions here.

As part of routine maintenance I'll be replacing the differential cover gasket on my 1968 Amazon 131. Which oil / fluid should I use to refill it? It has overdrive; does this make any difference?

Brookhouse states SPICER DIFF COVER GASKET. FITS ALL AMAZON & P1800 MODELS, but they have a foot note which advises (YOU MUST CHECK WHICH MAKE OF AXLE YOU HAVE FITTED). Is this a contradiction if it fits ALL Amazons?

Thanks.

I would use the current volvo hypid axle oil from the dealer or castrol Syntrax 75w/90 which is excellent being synthetic and will last for a long long time and reduce frictional losses in the axle .compared to EP90.

http://www.ebay.co.uk/itm/Castrol-Sy...4AAOxyBotTbNYa