I have seem to become a track addict. I need some advice and have done a search and not found what I am looking for. I know that driving a road track is much harder on your car than just daily driving, so I know I can't use the mileage for how often to change my fluids.

Can you help determine the number of road track days (80-90 min/day of track time) one should consider to change:
- Motor Oil
- Brake Fluid
- Transmission
- Radiator fluid
- Differental

My thoughts are:
- Motor oil - every 4 track days
- Brake fluid - bleed before every event, fully flush every 90 calander days
- Transmission - every 8 track days
- Radiator fluid - every 8 track days
- Differental - every 6 track days

Any help would be great.

 

Help?

 

I think you may be over-thinking things a little... but its always a good insurance policy to keep a close eye on all the fluids. With a modern engine like the VQ, when used with a quality synthetic oil, even with track days mixed in, I don't think its that imperitive to change it. Now... when/if you start running race gas, or for whatever reason use a rich fuel mixture, the oil can get diluted... I'd check it every-so-often, if it looks like its getting dark and/or black, then its time to change it. If it looks normal and clean, you should be good to go.

The brake fluid will depend on what kind of fluid you use, and your braking style. Many people are able to use something like Motul 600 or AP550 and use it all season, others boil their fluid every time out... you description above is a good starting point I think.

Tranmission/differential fluids really should only be changed once a year... even under heavy use. I would recommend flushing the system with a good synthetic like Redline or Amsoil.

Radiator... can't hurt, but probably not necessary... once at the beginning of summer, once at the beginning of winter should suffice

 

I agree with Stack. Most fluids don't need to be changed so often. The guy at the quick lube only knows what the company preaches, not about internal combustion engines. Hey, your barber says you need a haircut every two months as well. I will change my oil after maybe a half dozen track days (road course). I bleed the brakes before every event (I'll also measure the pad thickness). It's the thing I rely on most, so no chances there. The total flushing is taken care of by the frequent bleeding. I have changed the diff once and have no plans for further maint. The trans I have not done anything with, maybe this winter, but my shifting is limited, mainly 3rd, 4th & some 5th. The trans also has plenty of time to cool between those shifts. For the coolant I have no plans to change it. Maybe next year but only from a scale/corrosion stand-point, no cooling issues.

 

Stacy, your HPDE form actually says that the brake fluids have to be fully flushed 90 days before the event. Brake fluid absorbes water and lowers the boiling point of the brakes, since I live in the south and it is alway humid here, I figure you have to flush them every 3 months (even if you don't track the car).

It sounds like I have been overkilling it for all the other fluids. But it would be nice to get more peoples opinions on here.

 

I suppose I am a little more paranoid on the oil change. Even using Mobil 1 5w30 I changed probably once a month/2k regardless of events. You could send it out for analysis to find out how well the oil is performing over x time.
Brakes before any track event always bleed and checked for wear.
Others were a check and see.

 

I dont do too many track events, maybe 4 or 5 so my fluid change may be different.

I change my oil before every event, usually the month of or a couple of weekends before the event with Mobil One.

Brake fluid gets changed before every event also, usually the day before with ATE Super Blue.

Coolant flush once a year.

Havent changed the tranny fluid yet since, it's pretty new and only has about 10k miles on it, but will probably change this summer.

Diff fluid I change every other oil change with Royal Purple.

 

An oil analysis would be a great idea, but on my road race car, I changed the motor oil after EVERY full race weekend. All the other fluids I change every winter. I bleed the brakes as needed but only flush them once a year. You would be surprised how worked the oil gets in one weekend in hot weather.

 

As for me, I change the engine oil before every event and stick to the recommended 3,750 miles oil change for the filter.

Brake fluid gets bleed before every events and sometime I need to do it again after a particularly hard day. I do a full flush every year (RGS610)

I have Redline MT-90 in the tranny (Not to be had if you drive your car at or below 40F!!!) and RedLine HD Shockproof in the diff.

I drink plenty of Propel and Gatoraid all day...

 

yes that is a great idea. A sharp mind makes a sharp driver.

Let's see if I got this right for everyone:

- Change the motor oil before every track event
- Bleed the brakes before every track event, depending on track - bleed between days.
- Change Differental oil twice a year or about every 4 events
- Change the Radiator fluid once a year
- Change the transmission oil once a year

Is that about right?

 

I change my diff fluid at every oil change because the nismo diff produces a lot of heat. It runs smoother with fresh fluid.
Curious why you use shockproof in the diff. Redline told me to use the standard gear oil with limited slip additive rather than the shockproof in my nismo unit.

 

I use Redline 75w90 on the rear diff on my car, I got the same info you did. I use MT-90 on the transmission and Mobil 1 10w30 on the motor. And just switched to ATE Super Blue for the brake fluid.

 

My fluid change intervals are nearly identical to Stack's.

I change my oil (mobil1) and filter every 7500 miles or 5 track days, whichever comes first. If I don't do track days, I'd change out mobil1 every 10,000 miles. I'm not a cheapo, but that's pretty much what works for me for the past 15 years. I don't rely on the color of the oil since I've read that it doesn't represent oil condition.

I have two other cars that have 200,000 miles on the odo. Neither are track cars, but they don't get oil changes at less than 7500 intervals (w/ dino lube). I never expected any of these cars to last so long (and in some ways I wish they didn't because I want to buy a new car)

 

I have been talking to alot of mechanics and oil experts about motor oil. It is not the life of the oil that is the problem, it is the blow-by gases that create soot particles in the oil that are the problem. They say that regardless of oil used, you should change you oil often, and the best way is to see how black it looks. So I think I will stick to 2 to 4 track days (depending on the look) or 3000 miles.
So that being said, do you think synethic motor oil is really worth the price if we are changing it so often?

 

Synthetic is still worth it because its much more stable in high temps. If you're running at the track, synthetic will provide more protection.

 

Ever sent your used oil out for analysis. It's usually like 40 bucks for the full analysis. http://www.blackstone-labs.com/gas_engines.html

Their homepage also has a lot of info about impurities in the oil. Analysis after a few track days should let you know when the best time really is.

 

Changing the diff fluid of the OEM unit more than once a year is way overkill IMO. It's only a couple of gears spinning slower than the ones in the tranny. The VLSD unit is sealed anyways.

A clutch or torsen unit, things would be different. But on the OEM one? Nah

 

No clutch in my diff. So I want the maximum lubrification and don't need the additive.

 

Yeah, I sent a couple samples, I change oil every 2000miles, and on each sample I had about 4 track days, 15-20 1/4mile runs and the car is driven hard on the street (it's actually always driven hard )

motul 300v 5w40 with K&N oil filter, had virtually no wear and 0% insolubles. (I could definitely go longer tha 2000 miles)

if you have it analyzed for the first time, I reccomend the dyson analysis

 

Wow - I guess there is no rule for fluids change. But, everyones input has helped me guess what I will try and go from there. I just don't want to change the fluids that often since it cost a ton of $.