So as R12 excitement builds we are but a short three months away from another fabulous FGT rally during which we will see a number of owners with their new GT’s. It will be a very unique rally. And for roughly 50% of the attendees who did not attend Rally 6 in Utah previously, you are in for a special treat at Utah Motorsports Campus (UMC). Simply a beautiful track with 23 turns and long straights where the driver can exercise the FGT’s incredible speed. This post is targeted at the 05-06 owners wanting to go out on the track and experience the driving potential Ford gave us in the GT. The new GT owners may find this topic interesting but it does not pertain to them…yet.
As speeds can be high on the track at UMC so then must the braking ability be up to the task of pulling them down for the turns. It has been 11 years since our last 2006 GT rolled out of the production facility and hopefully most owners have flushed and changed their brake fluid. The Motorcraft DOT3 (part number PM-1-C) brake fluid originally installed in our cars is a perfectly fine and inexpensive brake fluid, if it is fresh. And by fresh I mean flushing out the whole brake fluid system and replacing it with new fluid. The whole FGT development program was completed using the Motorcraft fluid. The 05-06 FGT passed the demanding certification AMS 10 cycle DSTOP test without any special fluids, pads or tires. Parenthetically, the last three stops of this grueling 10 stop test resulted in the shortest braking distances. Ford gave us good brakes on our FGT. If you have not changed your brake fluid in the last 12 months, you really should give STRONG consideration to doing so.
Changing the fluid is a relatively easy process but if you do not feel comfortable performing this task take your GT to your local mechanic or dealer and have them do it for you. Brake fluid is “hygroscopic” meaning over time the fluid absorbs moisture from the atmosphere. It does this through the caliper piston seals (4 in each caliper) and the master cylinder cap which is vented. As moisture is absorbed into the brake fluid its resistance to boiling is lowered. When enough heat is put into the fluid (by hard braking) to cause it to boil you lose braking ability of the car. From my personal experience, this happened when I needed my brakes the most at the end of a long straight and a sharp upcoming turn. It will get your attention!
All North America brake fluids are controlled by the Federal Motor Carrier Safety Administration (FMCSA) Standard 116. All fluids are required (S5.2.2) to list the brake fluid’s “wet” Boiling Point (BP) (humidified fluid sample per S6.2). Most also list their “dry” (no moisture in the fluid) BP as a means of comparison with other fluids. When you frequently flush your brake system the hope is to have the fluid boiling properties more toward the dry side BP than the wet side. You do not have to select any special high performance brake fluid for your car (although you can easily move into a higher capability and more costly DOT4 fluid). What is most important is freshness. The OE DOT3 Motorcraft fluid has a dry BP of 500F at about $4 per 12oz container. The VERY best brake fluid is Castrol SRF which has a dry BP of 590F at about $62 for 34 oz. Everyone seems to have a favorite so just pick a fluid and have it changed.
A word about packaging. When flushing your brake fluid I suggest purchasing just enough new fluid to make the flush just prior to actually performing the transfer. Do not (ever) use a previously opened brake fluid bottle or one which may have been in your garage you bought years ago for another job. Buy specifically what you need at the time you intend to do the change. Unfortunately the plastic bottling most (but not all) brands use to package their fluid does have a Water Vapor Transmission (WTV) associated with the plastic. Over time sitting on the shelf, the fluid can absorb water vapor compromising the dry BP before you ever add the fluid to your brake system. This WVT can be made very low by selecting more costly plastic compounds but the permeability rate will never be zero as it is with metal packaging. ATE Type 200 is a good reasonably priced fluid (about $17 for 34 oz.) which is packaged in a metal container. There may be other metal container brake fluids as well. The key is again freshness. Whichever fluid you choose, purchase from a store which has a high product turnover. Although FMCSA Std 116 paragraph S5.2.2.1a mandates the fluid packager label each bottle with a manufacture date code I have never found these to be decipherable to any purchasing value. My advice, just buy fresh from a high volume stocking store.
Also while you have the rear wheels off the car for bleeding (inner bleed port first on our dual port Brembo’s) check the axle nut paint line with the mark on the axle shaft threads. When all our cars came off the assembly line this nut was marked to align with a line (also marked) on the axle threads. Make sure the two marks are aligned. If they are not then tighten the axle nut to again realign the match marks. The marks do tend to diverge with drive time so make sure they are aligned. If you have no alignment marks, my build book says the axle nut (35 mm socket) torque was to have been torqued to 400.0 Nm ± 30.0 Nm. And it was identified by Ford as a “critical” torque.
We will have a great time at UMC this year and performing some prior-event maintenance on your car will allow your total concentration to driving the track and enjoying your experience. One other important pre-rally topic is tires and that will be covered in an upcoming thread.
As speeds can be high on the track at UMC so then must the braking ability be up to the task of pulling them down for the turns. It has been 11 years since our last 2006 GT rolled out of the production facility and hopefully most owners have flushed and changed their brake fluid. The Motorcraft DOT3 (part number PM-1-C) brake fluid originally installed in our cars is a perfectly fine and inexpensive brake fluid, if it is fresh. And by fresh I mean flushing out the whole brake fluid system and replacing it with new fluid. The whole FGT development program was completed using the Motorcraft fluid. The 05-06 FGT passed the demanding certification AMS 10 cycle DSTOP test without any special fluids, pads or tires. Parenthetically, the last three stops of this grueling 10 stop test resulted in the shortest braking distances. Ford gave us good brakes on our FGT. If you have not changed your brake fluid in the last 12 months, you really should give STRONG consideration to doing so.
Changing the fluid is a relatively easy process but if you do not feel comfortable performing this task take your GT to your local mechanic or dealer and have them do it for you. Brake fluid is “hygroscopic” meaning over time the fluid absorbs moisture from the atmosphere. It does this through the caliper piston seals (4 in each caliper) and the master cylinder cap which is vented. As moisture is absorbed into the brake fluid its resistance to boiling is lowered. When enough heat is put into the fluid (by hard braking) to cause it to boil you lose braking ability of the car. From my personal experience, this happened when I needed my brakes the most at the end of a long straight and a sharp upcoming turn. It will get your attention!
All North America brake fluids are controlled by the Federal Motor Carrier Safety Administration (FMCSA) Standard 116. All fluids are required (S5.2.2) to list the brake fluid’s “wet” Boiling Point (BP) (humidified fluid sample per S6.2). Most also list their “dry” (no moisture in the fluid) BP as a means of comparison with other fluids. When you frequently flush your brake system the hope is to have the fluid boiling properties more toward the dry side BP than the wet side. You do not have to select any special high performance brake fluid for your car (although you can easily move into a higher capability and more costly DOT4 fluid). What is most important is freshness. The OE DOT3 Motorcraft fluid has a dry BP of 500F at about $4 per 12oz container. The VERY best brake fluid is Castrol SRF which has a dry BP of 590F at about $62 for 34 oz. Everyone seems to have a favorite so just pick a fluid and have it changed.
A word about packaging. When flushing your brake fluid I suggest purchasing just enough new fluid to make the flush just prior to actually performing the transfer. Do not (ever) use a previously opened brake fluid bottle or one which may have been in your garage you bought years ago for another job. Buy specifically what you need at the time you intend to do the change. Unfortunately the plastic bottling most (but not all) brands use to package their fluid does have a Water Vapor Transmission (WTV) associated with the plastic. Over time sitting on the shelf, the fluid can absorb water vapor compromising the dry BP before you ever add the fluid to your brake system. This WVT can be made very low by selecting more costly plastic compounds but the permeability rate will never be zero as it is with metal packaging. ATE Type 200 is a good reasonably priced fluid (about $17 for 34 oz.) which is packaged in a metal container. There may be other metal container brake fluids as well. The key is again freshness. Whichever fluid you choose, purchase from a store which has a high product turnover. Although FMCSA Std 116 paragraph S5.2.2.1a mandates the fluid packager label each bottle with a manufacture date code I have never found these to be decipherable to any purchasing value. My advice, just buy fresh from a high volume stocking store.
Also while you have the rear wheels off the car for bleeding (inner bleed port first on our dual port Brembo’s) check the axle nut paint line with the mark on the axle shaft threads. When all our cars came off the assembly line this nut was marked to align with a line (also marked) on the axle threads. Make sure the two marks are aligned. If they are not then tighten the axle nut to again realign the match marks. The marks do tend to diverge with drive time so make sure they are aligned. If you have no alignment marks, my build book says the axle nut (35 mm socket) torque was to have been torqued to 400.0 Nm ± 30.0 Nm. And it was identified by Ford as a “critical” torque.
We will have a great time at UMC this year and performing some prior-event maintenance on your car will allow your total concentration to driving the track and enjoying your experience. One other important pre-rally topic is tires and that will be covered in an upcoming thread.