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Discussion Starter · #1 · (Edited)
I went to a driver education event for a local track today and had a heck of a time. It was great and really showed the M5 in its element. However, I ran into a few problems.

(1) I boiled the power steering fluid
(2) Overheated
(3) Scalloped the tires

How I boiled the power steering fluid I really don't know. At first I thought it was brake fluid but followed the wet areas to the power steering fluid reservoir. So I cleaned it up and checked all the fittings and everything that I could see and get at without burning myself on the engine.

On the overheating, I don't know why this happened - I can only assume the thermostat is toast. I don't believe the wiring to my electric fan is wrong b/c I checked the wires and they look to be wired correctly.

Scalloping the tires; I sort of expected. Which is making me think really hard about a second set of tires just for racing. In fact, it is kind of making me realize I should probably look at getting an E36 M3 (and do a LSx swap?) just for track and occasional daily driving.

In general the event was a lot of fun and I suggest anyone who hasn't done a track day do it. I was keeping up with a Lotus Elise - mainly because the track was setup for cars with lots of torque and the lines were very open and flowing with the exception of a corner modeled after Monoco's Parade corner which required a heck of a lot of braking and turning after coming off a very soft fast turn.
 

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Wirelessly posted (BlackBerry8830/4.2.2 Profile/MIDP-2.0 Configuration/CLDC-1.1 VendorID/104)

How hot was it? I went out yesterday at Cal Speedway it was 98 had no issues thankfully
 

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I went to a driver education event for a local track today and had a heck of a time. It was great and really showed the M5 in its element. However, I ran into a few problems.
Boiling power steering fluid out of the reservoir is common, and happens more with 'sport' mode on.

Overheating, never experienced that on track even in severe temperatures. Are you saying you've removed your engine-driven fan and replaced it with an electric fan? It's possible that at track speeds it's too much of an airflow impediment.

The E39 M5 likes to understeer unless you use the right pedal energetically and the stock front camber settings are not too friendly to track use. What tires are you running and what pressures?
 

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the overheating and power steering issues all depends how hard your driving the car....and the enviorment to include air temp and track design or set up.

to the op... was it an auto x or were you on a real track? usually on a real track you will have plenty of air to cool both the ps and coolant. auto x's are harder on the car since they are usually small with a bunch of tight turns. this doesnt always allow enough airflow through the radiator, brake ducts etc.

ryan
 

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Two things on power steering fluid -- first you can turkey-baste out the contents of the reservoir and then fill with fresh fluid. Drive around for a while than then repeat the process. Do this 3 or so times, and you can pretty much get fresh fluid in the system. Second, there is a vent in the power steering reservoir cap that weeps out some fluid at track events and autocrosses. It makes kind of a mess, but the actual amount of fluid that comes out is very small. I use an old gym sock cut down and stretched over the reservoir top at events. It traps all the weeping, and you can see that it isn't much fluid.
 
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Second, there is a vent in the power steering reservoir cap that weeps out some fluid at track events and autocrosses. It makes kind of a mess, but the actual amount of fluid that comes out is very small.
This is true. On Ford products the standard approach is to drill the vent hole in the cap big enough for a 1/8NPT-to-hose-barb fitting, screw the fitting into the hole, then run a hose off into either a little catch-can or just around in a loop. As noted, it doesn't puke a lot.
 

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Discussion Starter · #7 ·
deknight said:
How hot was it? I went out yesterday at Cal Speedway it was 98 had no issues thankfully
It was mid 70s and that is why I was figuring something in my car was having issues.

Boiling power steering fluid out of the reservoir is common, and happens more with 'sport' mode on.
I don't use sport mode for driving events - the throttle is too jumpy (imo).

Overheating, never experienced that on track even in severe temperatures. Are you saying you've removed your engine-driven fan and replaced it with an electric fan? It's possible that at track speeds it's too much of an airflow impediment.
I have the Zionsville Super Duty Cooling kit w/ 2-speed fan. It wasn't too hot out today. I sure has heck hope it wasn't the spal fan since it should be able to pull more than enough air through the radiator.

The E39 M5 likes to understeer unless you use the right pedal energetically and the stock front camber settings are not too friendly to track use. What tires are you running and what pressures?
I had no understeer and I used the right pedal very energetically. I have a Dinan Stage 3 suspension setup and am running PS2s around 38 front and 40 rear.

rneedham1979 said:
the overheating and power steering issues all depends how hard your driving the car....and the enviorment to include air temp and track design or set up.
I drove the car hard, but with mechanical empathy (if that makes any sense).

to the op... was it an auto x or were you on a real track? usually on a real track you will have plenty of air to cool both the ps and coolant. auto x's are harder on the car since they are usually small with a bunch of tight turns. this doesnt always allow enough airflow through the radiator, brake ducts etc.
It was a real track, I don't take the M5 to autox (co-drive a Miata for that). There should have been more than enough air to cool everything so that is why I was thinking the thermostat died or something along that line.

CSBM5 said:
Two things on power steering fluid -- first you can turkey-baste out the contents of the reservoir and then fill with fresh fluid. Drive around for a while than then repeat the process. Do this 3 or so times, and you can pretty much get fresh fluid in the system. Second, there is a vent in the power steering reservoir cap that weeps out some fluid at track events and autocrosses. It makes kind of a mess, but the actual amount of fluid that comes out is very small. I use an old gym sock cut down and stretched over the reservoir top at events. It traps all the weeping, and you can see that it isn't much fluid.
Ok, that is good to know. Rather interesting that they would allow ps fluid to weep out of the reservoir.
 

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this sounds like a normal track day in an hard driven e39 M5.

PS fluid. I boiled mine once. Then flushed out the system with (either) mobil 1 synthetic atf or redline synthetic ps fluid (i can't remember which i used, and have a bottle of each on a shelf in my garage). There already exists a small vent hole in the p/s res cap. You can stick a small plastic drip irrigation fitting and some tubing to that, make a loop to catch any over flow. Never had a mess sinces.

Overheating: first the oil temp creeps up, then coolant temp follows. You need to short shift on some straights to get the revs down a bit, the temps will drop. You can ballance things so that your oil temps don't exceed 250-270F and then the cooling system can handle the coolant temps.
You've got to keep an eye on it though, it happens. If you're running TWS oil, switching to bmw long life synthetic 5w30 will drop your oil temps 10-15F and allow it to cool down quicker (assuming post 3/00 build date). Perhaps running the heater will buy an little extra time before the temps become critical.

Only real solution would be to ditch the factory coolant/oil heat exchanger and get a "real" oil cooler. Dinan is the only one who offers this, we've had threads about other alternatives but they've never happened yet.
 

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Discussion Starter · #9 · (Edited)
this sounds like a normal track day in an hard driven e39 M5.
This is both good and bad to know. I'm depressed a little because I figured the M5 should be able to handle the heat better than what it does; but, I'm glad to know other people are experiencing the same thing as well.

PS fluid. I boiled mine once. Then flushed out the system with (either) mobil 1 synthetic atf or redline synthetic ps fluid (i can't remember which i used, and have a bottle of each on a shelf in my garage). There already exists a small vent hole in the p/s res cap. You can stick a small plastic drip irrigation fitting and some tubing to that, make a loop to catch any over flow. Never had a mess sinces.
Do you happen to have a picture of your setup on this?

Overheating: first the oil temp creeps up, then coolant temp follows. You need to short shift on some straights to get the revs down a bit, the temps will drop. You can ballance things so that your oil temps don't exceed 250-270F and then the cooling system can handle the coolant temps.
I was keeping an eye on it somewhat, when it would hit the mark between 210f and 300f I'd back off of the car; but the car still dinged at me for coolant temps.

You've got to keep an eye on it though, it happens. If you're running TWS oil, switching to bmw long life synthetic 5w30 will drop your oil temps 10-15F and allow it to cool down quicker (assuming post 3/00 build date). Perhaps running the heater will buy an little extra time before the temps become critical.
I'm running TWS right now. The change to 5w30 might be the way to go since I have a 10/00 build date.

Only real solution would be to ditch the factory coolant/oil heat exchanger and get a "real" oil cooler. Dinan is the only one who offers this, we've had threads about other alternatives but they've never happened yet.
I'll have to do a search and read up on these threads.
 

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I went to a driver education event........However, I ran into a few problems.............(2) Overheated.........On the overheating, I don't know why this happened - I can only assume the thermostat is toast. I don't believe the wiring to my electric fan is wrong b/c I checked the wires and they look to be wired correctly..........

In general the event was a lot of fun and I suggest anyone who hasn't done a track day do it. I was keeping up with a Lotus Elise - mainly because the track was setup for cars with lots of torque and.........
On the overheating...assuming the fluid level was proper, I would first verify the electric fans are running when you're flogging the car and running hot. Checking wires will not thoroughly verify motor function, sensors, relays and DME outputs. If the fluid and electric fans appear in order, I would strongly suspect your mechanical fan clutch is defective. They go bad and few mechanics can recognize it. When the car is real hot, it should be fully-engaged and it will sound like a wind tunnel or huge vacuum cleaner with strong suction. A bad clutch will cause the fan to spin at a much lower RPM and the strong vacuum wind sound will not be present. Contrary to popular belief, a mechanical fan does do work at triple digit speeds.

As far as keeping up with an Elise, it's probably driver skill you're measuring. Straightaway acceleration can be compared, but if they are skilled, they will vanish from your view after a couple turns because their cornering & entry/exit speed capability is wicked. For that matter, a strong driver in a Neon will embarrass an HPDE novice in an M5. Elise is easily capable of midpack in A class, so lap times with experienced driver will crush any newbie running a Z06, Viper or serious Ferrari in C or D.
 

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Discussion Starter · #11 ·
On the overheating...assuming the fluid level was proper, I would first verify the electric fans are running when you're flogging the car and running hot. Checking wires will not thoroughly verify motor function, sensors, relays and DME outputs. If the fluid and electric fans appear in order, I would strongly suspect your mechanical fan clutch is defective. They go bad and few mechanics can recognize it. When the car is real hot, it should be fully-engaged and it will sound like a wind tunnel or huge vacuum cleaner with strong suction. A bad clutch will cause the fan to spin at a much lower RPM and the strong vacuum wind sound will not be present. Contrary to popular belief, a mechanical fan does do work at triple digit speeds.
The fluid levels were all proper, I checked them the night before and then checked them after the car dinged at me (letting it cool down some before checking the coolant levels).

I only checked the wires since that was all I was going to stick my hands into a hot engine bay. When I take it to the shop I'll ask them to verify the electric fan on the radiator goes into both low and high speeds.

I have no mechanical fan in my car, so it would be hard for the fan clutch to go out.

As far as keeping up with an Elise, it's probably driver skill you're measuring. Straightaway acceleration can be compared, but if they are skilled, they will vanish from your view after a couple turns because their cornering & entry/exit speed capability is wicked. For that matter, a strong driver in a Neon will embarrass an HPDE novice in an M5. Elise is easily capable of midpack in A class, so lap times with experienced driver will crush any newbie running a Z06, Viper or serious Ferrari in C or D.
Mostly it would be driver skill, but layout of the track, etc. also play into it. I know I would get burned by any driver better than me. I was getting passed by a spec miata one of the instructors was driving. It was just nice to know the M5 is a lot more competent at the track than what its 4000lbs. weight leads you to believe.
 

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.........It was just nice to know the M5 is a lot more competent at the track than what its 4000lbs. weight leads you to believe.
As Ryan mentioned, the M5 works perfect for occasional HPDE. It's body and roof structure is so strong that a roll cage is hardly necessary. The M5's extra weight just gives the tires & brakes a serious workout if you're pushing it hard for more than 5 laps. That's not what HPDE is about anyway. HPDE participants should not be running hot laps for 30 minute sessions at 100% because murphy's law will eventually catch up with them. An occasional lap at 100% in order to check min lap time is much safer and less abusive to hardware.

The new M3 only weighs about 300lbs less. Supra Turbos push 3800lbs with roll cage. The new Mustang Shelby GT500 weighs same as E39 M5. These cars are popular choices for track.

Car choice for HPDE should be driven by how often you participate, finances and your personal goals. If you run often and push to the limit, a dedicated track car makes sense. If you only occasionally attend track events to hone your driving skills, a premium performance luxury car is probably perfect, and cheaper. Tracking an expensive vehicle creates some financial exposure, whether it be a Corvette, Lotus or BMW. Very few insurance companies will cover collision losses anymore on a dedicated track.

This is why serious track junkies generally choose a dedicated track car for use on weekends that they can afford to stuff into the tirewall. A number of expendible cars in the $7k-$10k range can offer parity (or better) with E39 M5 on a road track, including lightly-modified 944T, C4 Corvette etc. It is difficult to upgrade M5 brakes, exhaust and wheels for the cost of one of these and upkeep is cheaper too. Running your street car on Sunday and trying to use it to commute to work Monday can be a bit tricky. I've had brakes wear down to backing plates (on the drive home) more than once. This goes for all car marques & models of course. I've tried it both ways...there's pros and cons.:dunno:
 

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Discussion Starter · #14 ·
As Ryan mentioned, the M5 works perfect for occasional HPDE. It's body and roof structure is so strong that a roll cage is hardly necessary. The M5's extra weight just gives the tires & brakes a serious workout if you're pushing it hard for more than 5 laps. That's not what HPDE is about anyway. HPDE participants should not be running hot laps for 30 minute sessions at 100% because murphy's law will eventually catch up with them. An occasional lap at 100% in order to check min lap time is much safer and less abusive to hardware.
This is what I experienced. I'm glad it was only what it was.

The new M3 only weighs about 300lbs less. Supra Turbos push 3800lbs with roll cage. The new Mustang Shelby GT500 weighs same as E39 M5. These cars are popular choices for track.

Car choice for HPDE should be driven by how often you participate, finances and your personal goals. If you run often and push to the limit, a dedicated track car makes sense. If you only occasionally attend track events to hone your driving skills, a premium performance luxury car is probably perfect, and cheaper. Tracking an expensive vehicle creates some financial exposure, whether it be a Corvette, Lotus or BMW. Very few insurance companies will cover collision losses anymore on a dedicated track.

This is why serious track junkies generally choose a dedicated track car for use on weekends that they can afford to stuff into the tirewall. A number of expendible cars in the $7k-$10k range can offer parity (or better) with E39 M5 on a road track, including lightly-modified 944T, C4 Corvette etc. It is difficult to upgrade M5 brakes, exhaust and wheels for the cost of one of these and upkeep is cheaper too. Running your street car on Sunday and trying to use it to commute to work Monday can be a bit tricky. I've had brakes wear down to backing plates (on the drive home) more than once. This goes for all car marques & models of course. I've tried it both ways...there's pros and cons.:dunno:
Yes, I'm beginning to realign what I wanted to get for a second car based on how much I've enjoyed tracking the M5. I'm trying to find something that I can track and then occasionally drive during the week. Like I mentioned above, the E36 M3 is looking to be an ok choice based on the price they are selling for now. Of course, as you said, there are pros and cons and they just have to be weighed.
 

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Rick once agin i agree with you 100%. It is fun keeping up and passing cars that cost 2-3 times more than the M5 and that are pretty much designed for the race track... In my limited expeireince the M5 has busted some serious *** on the track, after a few laps going full out it does expeirence some issue. I have been rather lucky and I think VIR (full course) really helps keep the vehicle temps down to include cooant, oil and brakes. I have given my car a bunch of full out laps at VIR without the oil temp or coolant temp getting much higher thanit does during normal driving. I havent been on the track when it has been to hot though, I think low to mid 80's is as hot as she has seen on the track. I really think the long straights help the car tremedously. I think If i did a smaller course or even an auto-X I would have issue with cooling on full out laps.


Ryan

As Ryan mentioned, the M5 works perfect for occasional HPDE. It's body and roof structure is so strong that a roll cage is hardly necessary. The M5's extra weight just gives the tires & brakes a serious workout if you're pushing it hard for more than 5 laps. That's not what HPDE is about anyway. HPDE participants should not be running hot laps for 30 minute sessions at 100% because murphy's law will eventually catch up with them. An occasional lap at 100% in order to check min lap time is much safer and less abusive to hardware.

The new M3 only weighs about 300lbs less. Supra Turbos push 3800lbs with roll cage. The new Mustang Shelby GT500 weighs same as E39 M5. These cars are popular choices for track.

Car choice for HPDE should be driven by how often you participate, finances and your personal goals. If you run often and push to the limit, a dedicated track car makes sense. If you only occasionally attend track events to hone your driving skills, a premium performance luxury car is probably perfect, and cheaper. Tracking an expensive vehicle creates some financial exposure, whether it be a Corvette, Lotus or BMW. Very few insurance companies will cover collision losses anymore on a dedicated track.

This is why serious track junkies generally choose a dedicated track car for use on weekends that they can afford to stuff into the tirewall. A number of expendible cars in the $7k-$10k range can offer parity (or better) with E39 M5 on a road track, including lightly-modified 944T, C4 Corvette etc. It is difficult to upgrade M5 brakes, exhaust and wheels for the cost of one of these and upkeep is cheaper too. Running your street car on Sunday and trying to use it to commute to work Monday can be a bit tricky. I've had brakes wear down to backing plates (on the drive home) more than once. This goes for all car marques & models of course. I've tried it both ways...there's pros and cons.:dunno:
 

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i tried to post a pic of my overflow loop but i can't because i've already posted them. If you do an advanced search with my username and powersteering fluid you should find the pics, probably from 03 or 04.

It was just a 90 degree drip irrigation fitting, and some drip irrigation hose and made a loop.
 

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i tried to post a pic of my overflow loop but i can't because i've already posted them. If you do an advanced search with my username and powersteering fluid you should find the pics, probably from 03 or 04.

It was just a 90 degree drip irrigation fitting, and some drip irrigation hose and made a loop.
 
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thanks, that's it there. A couple feet of drip tubing in a loop. Honestly, since flushing the system with synthetic, i've had no issues of it boiling over, but this tube seems to keep the residue off the ps reservoir.
 

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Discussion Starter · #19 ·
CSBM5 and mottati - thanks for the picture, if it boils over again I'll try this out.

Today I had the car checked out and changed the oil to Mobil 1 5w30, the p/s fluid replaced with Redline ATF, an o-ring in the oil pan replaced and the electric fan confirmed to be working correctly. The car does appear to run cooler based on the oil temp gauge on the way home combined with the 95*F weather the temp gauge didn't move past where it normally read for the 10w60 on a cool day.

rneedham1979 said:
...I think If i did a smaller course or even an auto-X I would have issue with cooling on full out laps.
When I did a few autoxs with the M5 there was ample time between the runs for cool down that the car never came close to going over its normal operating temperature. A small race track you'd have cooling issues since that is what I experienced.
 

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Then flushed out the system with (either) mobil 1 synthetic atf or redline synthetic ps fluid (i can't remember which i used, and have a bottle of each on a shelf in my garage).
What exact Redline product did you use? The TIS lists a whole bunch of "Dexron II D-xx" fluids as ok for initial filling and refilling of the powersteering. However, when I go to Redline's site, they have a choice of ATFs and "Power Steering Fluid" the last of which they give no details about it (it doesn't even appear to be a synthetic?).

Under their Automatic Transmission Fluid section, they have a number of products, and it appears that their D4 ATF would fit the spec (i.e. it lists Dexron II). However, it then has a listing for what they simply call "Synthetic ATF" which also says it is a Dexron II compatible fluid. This after the text describing the whole section starts off saying: "Red Line Synthetic Automatic Transmission Fluids are designed to provide..." which implies that they all are synthetics. :dunno:

So which to use? D4 ATF, Synthetic ATF or "Power Steering Fluid"?

Help? ouich

EDIT: I didn't see the link on the power steering fluid page for the data sheet. It is a synthetic power steering fluid meeting Dexron II-D requirements, so this looks like the one to get.
 
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