when do you need a diff and gearbox cooler?

[-ghost-]

So while doing the wiring today cut out all the diff wiring but then i got thinking will i need one but how do you know when you need one?

Same with gearbox

[Fake Ben Taylor]

Kev (sm) had his diff overheat on a trackday at not mega power.

The z is known for its diffs getting really hot as stock due to no cooler and im in the process of building a kit for mine using s body parts. And the z's diff is bigger than the s body one.

Id fit one straight away. Gearbox im not sure on

[BLAKTOOTH]

Kev (sm) had his diff overheat on a trackday at not mega power.

The z is known for its diffs getting really hot as stock due to no cooler and im in the process of building a kit for mine using s body parts. And the z's diff is bigger than the s body one.

Id fit one straight away. Gearbox im not sure on

How did he know it was overheating?

[Fake Ben Taylor]

Theres a warning light on the dash that comes on when the diff gets too hot iirc he had removed the cooler thinking it wasnt needed and then at a trackday, i believe oulton, the light came on as the diff was way too hot. I believe he refutted the oem stuff after that and never saw the light again

[Fake Ben Taylor]

It was many years ago so the specific details are hazy but the cooler is xefinitely needed

[Actual_Ben_Taylor]

How did he know it was overheating?

The S13 has a light on the dash for diff oil temp

More of an issue with the standard viscous diff IMO

[Zornyan]

As above, most sbody diff coolers don't actually work, when I pulled apart 3 different s13 ones all of them had so much dust and crap inside I don't think the pump had EVER switched on.

Never had s problem drifting an s13 with no cooler either. Personally I think an uprated cover with cooling fins will do just fine for most people.

[BLAKTOOTH]

I wish I'd checked my diff temps at Cadwell but I was having too much fun so forgot. I'm pretty sure it's exceeding what's considered acceptable though and that's with a larger back plate fitted. I'll definitely be investing in a cooler setup soon. One with a thermostatic switch. Certainly can't do any harm.

[Fake Ben Taylor]

ABT - arent plate diffs more susceptible to heat? Again on thr z's theyre overheating and causing excessive wear :/

Zornyan theres more strain on diffs when gripping than drifting i think as once traction is broken the strain on the diff reduces

[Actual_Ben_Taylor]

I was thinking more about the fact that if you overheat the viscous stuff it'll stop working properly.

[-ghost-]

Ok this is for more grip hill climb and time attack and track days.

1.5/2way diff

I have no light s14(since i just chopped all the diff wires i especially don't)

So i take it one of the sensors is for oil temp?

If so is the best way to get a thermostatic switch to turn the pump on so it's all automatic?

I take it a small 6 row mocal oil cooler would be fine?

[immy21]

The stock diff coolers come on when oil temps exceed a certain temp AND you are travelling over a certain road speed, I can't remember the exact figures, it's in the FSM but the speed was fairly high which seems why they rarely do anything.
Have a look at which of the two relay's in the rear quarter dealt with speed, bridge it and you have a thermostatic diff cooler.

I'v never done this, Petrol made a guide, search it out or look at FSM and work it out.

[Actual_Ben_Taylor]

What gauges have you got?

With an SPA or similar you could display diff oil temp and have it trigger the pump at a preset temperature

[Fake Ben Taylor]

I was thinking more about the fact that if you overheat the viscous stuff it'll stop working properly.

Ah i see! Good point

[-ghost-]

What gauges have you got?

With an SPA or similar you could display diff oil temp and have it trigger the pump at a preset temperature

Im trying to keep gauges to a minimum but I have a spare oil oil pressure and temp gauge its more the fact I'm really tight on space with the fuel tank and diffuser it would mean the oil cooler having to go where the stock fuel tank goes. so i'd rather plan for it now if i need one. My edu can control the pump as well I have a spare 12v that can turn a relay on tho it would be easier to just build a thermostatic switch as only 1 12v power feed is needed(less wiring woooo and less tracking if something don't work)

Does the car come with a diff oil pump I remember taking off the cooler but no pump?

[skyshack]

Im trying to keep gauges to a minimum but I have a spare oil oil pressure and temp gauge its more the fact I'm really tight on space with the fuel tank and diffuser it would mean the oil cooler having to go where the stock fuel tank goes. so i'd rather plan for it now if i need one. My edu can control the pump as well I have a spare 12v that can turn a relay on tho it would be easier to just build a thermostatic switch as only 1 12v power feed is needed(less wiring woooo and less tracking if something don't work)

Does the car come with a diff oil pump I remember taking off the cooler but no pump?

All UK spec S13 and S14 have a pump and cooler. S13 has finned cover as well, extra 0.6L of fluid. Even on open diff.

When a Viscous diff is locked it's not slipping so don't make heat. If you keep grip and the diff doesn't lock it gets hotter - that's a track day. Heat is down to power lost in gear mesh and wheel rotation speed for oil fling. Once traction is lost the power transmitted is much reduced - hence the rpm rise and wheel speed. Drift won't have a slipping diff taking sweeping 100mph corners.

The ZX TT has a gearbox cooler for manual trans. FAST shows 2 pumps on UK spec TT. One for gearbox and other for diff, found a diff cooler but not the one for the box. Of course everyone breaking a TT will leave the useless bits under the car and just cut the hoses.
ZX TT diff cooler

ZX TT trans pump but cooler? Sec 321 shows the banjos fit to the manual box case. Maybe it's just a lube circulation thing and length of pipe run does the cooling. Wonder how often anyone has changed the filter?

Part 21690-37P00-
http://www.partsbase.org/parts/nissan-2169037p00/

VW had a good shout about the number of coolers on Veyron but Nissan 300ZX got there first with cooler overkill - rad, A/C, I/C, trans and diff. Most of the additional ones the Veyron has are due to splitting them left and right, counting charge coolers and their rads separately but the overworked spoiler needed one too.