Cool Running With Shell Spirax

Cool Running With Shell Spirax


Choosing the right lubricant has a direct impact
on gearbox performance. The desire for improved fuel economy through increased
transmission efficiency has led to the development
of lower viscosity grades. At 20 degrees centigrade
an SAE 75W-90 lubricant would have a much lower viscosity than a traditional
SAE 85W-140 lubricant. The impact of viscosity grade is clearly seen
in thermal imaging of the gearbox as it warms up. On the left
the demonstration gearbox is filled
with Spirax S6 AXME 75W-90 and on the right, Spirax S2A 85W-140. For this demonstration, the lightly loaded gearbox
is run at 2,000rpm for 50 minutes. Once warmed up,
the maximum temperature reached, using the SAE 85W-140 oil, was 45 degrees centigrade. The maximum temperature reached
using the SAE 75W-90 oil was 32 degrees centigrade. After 52 minutes the input speed
was accelerated to 3,000 rpm, which led to a further increase
in temperature. Once the gearbox is fully warmed up, the temperature
of the more viscous SAE 85W-140 oil is approximately
10 degrees centigrade higher than that of the SAE 75W-90. This temperature difference is due to the lower friction
of the SAE 75W-90 oil. Filming the Perspex gearbox, with an ultra-high-speed
video camera, enables oil flow visualisation. Both the Spirax
S6 AXME 75W-90 lubricant and the Spirax S2A 85W-140 lubricant adequately lubricate all
the important parts of the gearbox from start-up in a very short time. However, there are subtle differences
between the oils in terms of amount of oil in the sump and how quickly
lubricant returns to the sump. Using Shell Spirax lubricants ensures good lubrication
for your gearbox. Choosing a high performing,
low viscosity Shell Spirax lubricant can offer cooler operation, higher gearbox efficiencies, and improved fuel economy, as compared
to traditional high viscosity oils.

48 thoughts on “Cool Running With Shell Spirax

  1. I noticed more cavitation with the thinner oil, although the friction is reduced, the oil looks like it would break down quicker.

  2. ما هو الزيت المستخدم في علبة السرعة لتركس الجنزير فيات الس 12 ج

  3. That's quite some useless test.
    Gearboxes are connected to hot engines,all the time….
    giving temperatures out of nowhere is dumb.

  4. All this video does is reveal whats already been know….. That heavier viscosity lubricants will always run hotter merely because of the higher friction and force necessary for the gear assembly to move through it. That doesnt mean its not more fitting for a specific application either, because if load is high enough and capacity is small enough, higher viscosity will outperform a lower viscosity in maximum running temps. So people…..dont go swapping fluids around in your vehicles until you confirm what fluids will or wont work in your vehicle.

  5. Hello Shell. Is there any comparison about mono and multi viscosity oils and some information about pitting in gearing teeth?

  6. 3,000 rpms is nothing to a transfer case crank that baby 5,500 rpms and lets see that thermal and visual then i will be colored impressed

  7. Surely Shell doesn't still sell Spirax, we use to use that over 30 years ago. It was the best gearbox oil back then though.

  8. Generally wouldn't use 85w/140 in a gearbox. Used in Final drive conventional differentials. Not used in combined gear/ final drive transmissions either because viscosity is far too high for syncrohmesh operation.

  9. If I'm not mistaken viscosity 140 is for gearbox like differential so I think even I've got lower temp using viscosity 90 on differential the viscosity is mismatch then I would be in trouble in latter time

  10. I have been using Shell 15 w 40 rotella in everything from my Toyota 4 cylinder to my lawn mower.I have no complaints.Also use it in three different diesel from Kabota to Detroit diesel.

  11. Now take the temperature of the metal gears itself. The conventional oil will show a lower temp on the gears, it acts as a heat sink to pull heat away from the metal.

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