Mark you calendars… Saturday April 19th @ 4:30PM for a Pre Season Cue and view












RennWerks Performance,#becausebags, and Spring Autoworks invite you to join us as we host a pre season barbecue/car show.  Bring your ride or just come out to enjoy the afternoon and show your support.


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Transmission Maintenance & Service

BMW ZF HP-18 Transmission being repaired

BMW ZF HP-18 Transmission being repaired

Maintenance schedules offered by car manufacturers should include the transmission. Car owners beware: Many manufactures such as BMW, Lexus, Mercedes, Audi, and now, Cadillac, state that their transmissions have lifetime fluid. Lifetime, in car speak translates to “life of the warranty.” Their transmissions should still be serviced at least every 40,000-60,000 miles. Transmission fluid plays a critical role in how a transmission functions and the car part longevity. Like engine oil, transmission fluid should be checked and changed on a regular basis; however, the interval is different for all vehicles and dependent on the transmission and fluid type as well as use.

Most experts feel severe use warrants a recommended 20,000-30,000 mile fluid and filter change interval. Severe use is defined as more than 50 percent use in heavy city traffic or with ambient temperatures above 90 degrees Fahrenheit, we also recommend changing the fluid whenever there is an indication of oxidization or contamination. Most modern transmissions, including ZF models used by GM, BMW, Audi, Porsche, and Mercedes-Benz use an aluminum valve body and magnesium housing. This soft metal is less tolerant of dirt and abrasives and GM recommends more frequent fluid changes to prolong the life of this auto part.

In the old days, generally, the car was lifted on a hoist, the transmission pan was dropped and the old fluid pours out. The fluid and the pan are inspected for contaminants, such as fiber from clutch discs or any other indication of a larger issue that may be appearing.  After a routine check of the exposed components the filter is changed, the pan is replaced and the fluid added to the proper level.  In modern times, changing transmission fluid is not as simple as changing engine oil and should be handled by a service technician or someone with a thorough understanding of transmissions. Modern cars and luxury vehicles have complex computer controlled  transmissions that require using diagnostics systems to communicate with them  and special functions and procedures for the service. Any fluid remaining in the torque converter and other parts of the transmission should be flushed using a special machine.

BMW Transmission Pan With Dirty Fluid and Debris at 35,000 miles

BMW Transmission Pan With Dirty Fluid and Debris at 35,000 miles

Manual transmission fluid change is usually simpler. Manual transmissions are usually outfitted with drain and fill plugs. The car is lifted, the oil drained, and then refilled with the proper grade specified by the manufacturer. If an owner decides to tackle this operation on his or her own, one thing to remember is to make sure the fill plug can be removed and the fill tube is clear before draining.

While periodic fluid changes are ideal, checking the fluid level and condition on a regular basis is a good idea as well. Older automatic transmissions have a dipstick similar to the engine oil dipstick. Modern transmissions can only have the fluid level checked with manufacturer specific electronic scan tools. However, unlike engine oil, the car must be running to check the level. The vehicle manual may also specify if the car should be in park or neutral, and what temperature the transmission should be — fluids expand with temperature and checking a cold transmission will often provide a false reading. When the dipstick is out, smell the fluid and note if it smells burned (a symptom of overheating), or like any other fluid (gas, coolant or motor oil), which may be a symptom of a leak in the system or contamination. Also, wipe some of the fluid onto a piece of white paper or cloth and check the color against a fresh fluid sample. Too much variation in color could mean contamination or degradation of the fluid.

Manual transmissions can be checked by opening the filler plug. The level should be just below this hole. Dip a cotton swab in, pull some fluid out, and smell it to check the condition of the oil just as you would on an automatic transmission.

While maintenance is key to auto part longevity, being aware of any bangs, whines or groans from the transmission, as well as smells, will help head off any problems at an early stage.

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Get “Bagged” and slam your German car in style

yih front

In the American car market, the “Fast and the Furious” days appear to be long gone. It seems that strict smog laws and being environmentally conscious have changed automotive style and car culture trends.

There has always been car subcultures in which “low and slow” was the way to go. The Lowrider lifestyle from the early 80′s , which for the longest time was considered a gangster thing only, kept a lot of things out of the mainstream. Putting a car on hydraulics was the way to go. However, hydraulics gave the car a harsh ride and poor handling characteristics. The small 14inch and 15inch wheels of the day didn’t help either.

Old school American muscle hot rods were becoming expensive and hard to get and by the late eighties, most of the cars being produced from Detroit were terrible. The imported cars from Japan gained a lot of traction in the market and were affordable and thanks to the Japanese Market were easy to modify.

Bring in the nineties, and race inspired coilover suspensions became accessible and the dangerous technique of cutting springs in order to lower a car faded. Thanks to the Japanese car enthusiast, a lot of trends that were only seen in Europe and Japan spilled over into the American European car market. It was a hot thing to see lowered E30 Bmw all done up in Ac Schnitzer, or a Mercedes tricked out with mesh BBS wheels and polished lips, or and Audi setup with in rally style body panels and small wheels with fat tires. The fiberglass body panel industry went over board with all the crazy ground effects kits and aggressive vents (some were comical) started by the Ferrari Testarossa.

Move forward to 1997 when OBD II emissions laws were introduced and complex fuel injection systems and it wasn’t hard to see that things were gonna change. At the turn of the century, it was getting painful to get horsepower to match the tight suspension. The roads are terrible and every time you hit a pothole it was almost guarunteed that you would have to drop fat cash for new wheels. Putting DUBS and other large diameter wheels on your car is the thing, but the stiff lowered spring suspensions put your investment at risk on public roads. Scraping your car on speed bumps and driveways also sucked.

Fast forward to today and airbag suspensions give you the best of both worlds, style and a nice riding vehicle. Airbags were once scorned by low riders for not being fast acting and they were unreliable. High-end automobile manufacturers such as Cadillac, BMW, Mercedes-Benz, and Audi brought them to the market for their luxury cars and SUV ‘s. Now you can ride in style and with a flick of a switch, you can elevate your car to a normal height to get around obstacles. The new systems like, AccuAir, are computer controlled, and have done away with the problems from the old days.

yih ass

Specialists like James Osborn of Sprint Autoworks ( #becausebags) have really grabbed hold of the trend and are taking it to the next level. We, at RennWerks, applaud the effort and welcome the trend. We have always appreciated the look of a slammed ride and have always desired a car that rides comfortably when not at the race track.



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Consumers need to advocate for Automotive “Right to Repair” laws in the aftermarket.

We are posting an article written by Brian Albright for to help give it exposure and traction.

“Right to Repair” laws are laws being pursued to allow aftermarket and independent repair shops to have unhindered access to the same software and repair information as the dealerships without biased penalties and costs. Such laws can be of great benefit to consumers in terms of repair costs, as it will allow independent shops and aftermarket suppliers to compete on more fair level with the dealerships and be able to provide better and more comprehensive service to their customers. Ultimately, the voice of consumers are going to be needed to move things forward.

How Right to Repair went nationwide

Aftermarket, OEM groups sign agreement to provide repair information access
Tuesday, February 25, 2014 – 08:00

When both the electorate and legislature in Massachusetts passed the state’s Right to Repair law in November 2012, it was clear that the industry had turned a corner in what had been a lengthy battle over access to manufacturer repair data by independent repairers.

For Right to Repair supporters, the passage had big implications for their efforts elsewhere in the country. If OEMs had to abide by the rules in Massachusetts, it made little sense for them to do things differently elsewhere. In January, the other shoe dropped, and a coalition of both OEM and aftermarket industry organizations signed a 50-state memorandum of understanding (MOU) that unofficially expands the Massachusetts requirements nationwide.

The Alliance of Automobile Manufacturers, the Association of Global Automakers, the Automotive Aftermarket Industry Association (AAIA), and the Coalition for Automotive Repair Equality (CARE) based the agreement directly on the Massachusetts law. The MOU extends the essential provisions for light vehicles, and covers all companies and organizations that are members of the signatories. The OEM groups represent nearly all of the major automotive manufacturers.

“Our goal has been to get a national agreement with manufacturers, so that we wouldn’t need to go state by state anymore,” said Aaron Lowe, vice president of government affairs for the AAIA. “We’ve been negotiating this for some time, and one of the sticking points was seeing how things would be finalized in Massachusetts. We worked with the trade associations on an agreement that all the manufacturers would pledge to uphold, and it’s based on the Massachusetts law.”

The agreement came on the heels of another Right to Repair law passing the New Jersey Assembly. Under that bill, manufacturers would have had to make all technical information available for purchase for model years made after 2002. Violations could result in fines of $10,000 for the first offense, and $20,000 for subsequent violations. The law would have also banned manufacturers from requiring dealers to purchase information in a proprietary format under less favorable terms than the information is available to other purchasers.

With the signing of the MOU, all the organizations have agreed to drop their state-by-state efforts, and have called on state-based groups to halt any legislative activity that could undermine the agreement.

“Much like with fuel efficiency economy and greenhouse gases, a single national standard regarding vehicle repair protocols is imperative,” said Mike Stanton, president and CEO of the Association of Global Automakers.  “A patchwork of fifty differing state bills, each with its own interpretations and compliance parameters doesn’t make sense. This agreement provides the uniform clarity our industry needs and a nationwide platform to move on.”

According to a document released along with the MOU announcement, the AAIA and CARE have agreed to oppose any additional state efforts while the MOU is being implemented: “While AAIA and CARE would prefer a right to repair law, both groups believe that such a lobbying effort would take years to accomplish as well as significant resources. All groups felt that both the aftermarket and consumers would benefit more by devoting its resources to implementing a voluntary agreement.”

Under the MOU, OEMs must make available under “fair and reasonable terms” the same tools, software, and repair information that is available to franchised dealers; beginning with the 2018 model year, they must establish Web sites or clouds that contain the same information and software that dealers have access to as part of their proprietary tools; and car companies must provide access to diagnostic computers using a standardized vehicle interface that meets either the SAE J 2534 or ISO 22900 standards.

The agreement applies to all automobiles under 14,000 pounds, excluding motorcycles.

Since this is an agreement rather than a law, participation is still entirely voluntary. If a repair shop finds it can’t access an automaker tool or software, they can contact the car company directly or via the National Automotive Service Task Force (NASTF) to request access. If they are not satisfied after 30 days, they can take the issue to a Dispute Resolution Panel established under the agreement. The panel would include two members appointed by automakers, and two members appointed by CARE and AAIA. A fifth neutral member would serve as chair.

“This isn’t the same as having a law in every state, but we’re going to have a dispute resolution process to handle any issues that might arise with the manufacturers and repairers,” Lowe says. “Both the manufacturers and the aftermarket are ready to move on. The issue was resolved in Massachusetts, and the manufactures know they will have to comply. We will make the agreement work in all 50 states, and the manufactures have signed on to do the same.”

The NASTF was established by the Alliance of Automobile Manufacturers and Association of International Automobile Manufacturers, along with the Automotive Service Association (ASA), to provide a way for service shops to buy vehicle service information via subscription. The ASA has uniformly opposed Right to Repair legislation, and did not participate in the current MOU.

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How ‘High-Tech’ Is the Automotive Industry and Your Audi, BMW, and Mercedes Car. A recent Study Provides Answers.

We all know that the automotive industry is ‘high-tech.’ If you’ve ever wondered just how high-tech it is, the results of a recent study provide some answers.

No matter if you’re an industry veteran, a newcomer or somewhere in between, you’ve undoubtedly heard references to today’s cars as being much more high-tech than their predecessors. But exactly how high-tech are these vehicles and the industry that builds them, and what the heck does high-tech really mean, anyway?

A newly released report by the Center for Automotive Research (CAR), a nonprofit research organization based in Ann Arbor, MI, helps to quantify these questions and more. The complete report is available online at

According to the report on the study, an industry sector can be considered high-tech if it possesses certain characteristics. A high-tech industry, for example, would generally have 10% or more of its workforce consisting of technical employees like engineers. Based on a series of prescribed criteria, the automotive industry is not only high-tech, concludes the report, “it is frequently a leader in technological developments and applications.”

Here are highlights from the study’s findings:

•An average vehicle contains around 60 microprocessors on as many as 4 different networks—four times as many as a decade ago.

•More than 10 million lines of software code run a typical vehicle’s computer network, or over half the lines of code that reportedly run Boeing’s 787 Dreamliner.

•Worldwide, automakers spend an average of $12,000 for research and development for every vehicle manufactured.

•Approximately 4800 patents are granted to the automotive industry every year.

•Six automakers—BMW, Toyota, Audi – Volkswagen Group, General Motors, Honda, and Mercedes.—are among the top 20 in all corporate research and development spending. GM and Ford individually spend more money on R&D than either General Electric or Apple.

•Vehicle electronics currently make up as much as 40% to 50% of the total cost of a vehicle, up from 20% less than a decade ago. The chart below illustrates the growth of electronic content in vehicles over the past 50-plus years.


The report suggests that an automobile is the most complex item most consumers will ever purchase, and that “the auto jobs of today and the future belong to those who have the advanced skills necessary for designing, building and maintaining the high-tech content inherent in motor vehicles.” If we accept these as facts—then the old basic skill level of the low wage mechanics seen at most tire chain stores, discount auto repair shops, quick lube places, and most general auto repair shops are on their way to extinction! The automotive industry is in a period of transition in which, highly trained technicians that require high pay and therefore increase labor rates are replacing old ways of doing business in the Auto Repair Industry.

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What Cars Attract Women?

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What if I never changed the oil in my European car?

Oil in an engine is vital to your vehicle. Without them, someone or something is going to die!

Oil is an essential lubricant in your engine.  It lets metal press against metal without damage.  For example, it lubricates the pistons as they move up and down in the cylinders.  Without oil, the metal-on-metal friction creates so much heat that eventually the surfaces weld themselves together and the engine seizes. This is not good if you’re trying to get somewhere.


Let’s say that your Audi or BMW engine has plenty of oil, but you never change it. Two things will definitely happen:


Dirt will accumulate in the oil.  The filter will remove the dirt for a while, but eventually the filter will clog and the dirty oil will automatically bypass the filter through a relief valve. Dirty oil is thick and abrasive, so it causes more wear.  Additives in the oil like detergents, dispersants, rust-fighters and friction reducers will wear out, so the oil won’t lubricate as well as it should. Residual fuel left over from cold starts and the combustion process eventually builds up in the oil and thins it out and breaks it down. Eventually, as the oil gets dirtier and dirtier, it will stop lubricating and the engine will quickly wear and fail.



<-Unserviced BMW Motor Valve Train with Sludge buildup from a lack of oil changes at 5000 mile intervals.





Also, all engines burn a little bit of oil over time. Eventually, you will run out of enough oil to properly lubricate your motor and the motor will have catastrophic damage. This is why all manufacturers recommend that you check your oil regularly. Usually, every other time you visit the gas station or 1000 miles. More recent cars from Porsche, BMW, Audi, Cadillac, Lexus, and exotics such as Ferrari, and Lamborghini should have their oil level checked every 300 – 500 miles.

BMW_ValveTrain_properly serviced<–Similar BMW Motor Valve Train  from a BMW that has been service at regular 5000 Mile intervals.

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Causes of High Oil Consumption in Your Mercedes-Benz

Examining the Causes of High Oil Consumption in Your Mercedes-Benz

If you have noticed that your Mercedes has been consuming more oil than usual, you are not alone. While cars generally consume more oil as their mileage increases, high oil consumption is a condition that has been increasingly found among newer, lower mileage vehicles, including European makes like Mercedes. Here are some possible causes of high oil consumption in your Mercedes-Benz.

MBZ, MBenz, Mercedes-Benz, ZDDP, BMW, Porsche, Audi








Low Quality Oil

High oil consumption can in many cases be attributed to the use of low quality oil. When choosing motor oil for your Mercedes, it is important to choose a brand that is high in lubricating metals like phosphorous and zinc. These metals are also referred to as ZDDP anti-wear additive. In recent years, drivers have increasingly been steered towards oils with greatly reduced ZDDP anti-wear additive levels on the grounds that high ZDDP anti-wear additive levels can cause catalytic convertor damage. The problem is that these oils simply do not sufficiently lubricate your engine’s moving parts, potentially leading to serious repair issues down the road.

Cheap Oil Filters

If you drive a European vehicle, it is important to use an oil filter that is able to fulfill your engine’s unique oil needs. For a Mercedes-Benz, for example, you should make sure to use oil filters from Mahle, Mann, or Bosch. Failing to use the right filter can either starve your engine’s moving parts of oil or lead to excessive consumption, both of which can increase oil consumption while decreasing fuel efficiency and performance.

If you notice that your Mercedes is consuming more oil than usual, consult with a mechanic who specializes in European vehicles as soon as possible. Your European luxury vehicle has unique needs that require specialized knowledge and products to optimize performance. To consult with a mechanic who specializes in Mercedes-Benz repairs, contact RennWerks of San Jose by calling (408) 370-7480.

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Women Can Get Steep Discounts at Auto Repair Shops!?


As a shop owner I make sure our policies are fair, ethical, and every patron is treated with the same respect and guidelines when quoting the cost of an auto repair and writing the initial estimate. It is difficult and time consuming to write and accurate repair estimate and track down the proper parts and their numbers, especially with European and German cars (Audi and Volkswagen being the worst). We have noticed a direct correlation between the sexes and the amount of time spent preparing the initial estimate. We find that helping women resolve the problems with their cars is much easier than men. Women just want the repairs done right and to not feel taken advantage of in the process, they tend to not get mired in the details and to micro manage us right out the starting gate. Men on the other hand, tend to think they already have all the answers and their hard-heads get in the way and often make it difficult and more time consuming to write a repair estimate. When it comes to service writing, my staff and I, find it often easier to consult with women, because they often make our lives easier and allow us to spend much less time getting hassled and focusing on writing the repair order for what is properly needed. Remember, time is money spent, and the service writer needs to be paid for his time. Because, we are saving time at the desk, and can quickly move on and resolve the customer’s complaint on their car’s issue. We are more inclined to give a discount for making our lives easier.

So, I thought it was funny and somewhat relevant when my sister e-mailed me the following article discussing gender differences and discount in the auto repair industry.

Women Can get Steep Discounts at Repair Shops
by Dan X. McGraw, Houston Chronicle Updated 11:26 am, Wednesday, June 19, 2013

Women may think mechanics are charging them more for routine car repairs, but a new study is punching some holes into
that stereotype.
According to a study by the Kellogg School of Business, female drivers get steep discounts at auto repairs stores more often than men.
The study found women who asked for a cheaper price got it 35 percent of the time.
Men, on the other hand, only got the lower price 25 percent of the time. Researchers said the disparity is likely due to cultural and
social norms.
“If on average women don’t ask [for a lower price], but this woman is asking, that’s quite different from what’s normally expected,”
researcher Florian Zettelmeyer said.
The study does find women have one major disadvantage when it comes to car repairs.
Women who claim to have no idea on the price of a repair are often given a higher price than a man making the same statement.
Researchers said the study found repair shops generally believe women know less about cars than men do.
“If you say ‘I have no idea’ and you’re a woman, you really have no idea,” Zettelmeyer said.
Men who claim to have no idea are generally given a cheaper price than women. Researchers say that’s true because of the mechanic’s
preconceived notion about men.
If you are a man, “maybe you’re being really strategic,” researcher Meghan Busse said in the study.
The inequalities in prices aren’t universal. Men and women are charged virtually the same price if they call a shop armed with information
about the cost of the repair.
Researchers say that information can help drivers get the best price.
Women should call several shops about the repair and ask for a discount. Men should try not to sound stupid.
“You would be wise to avoid engaging in any behavior that reveals” that you don’t know what you are talking about, the researchers wrote.

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Common Undercar Repair Tips for European Car Owners


  • Every year, people will install new brake pads
    and/or shoes, then reuse the old brake hardware. Constant tension, heat, friction
    and mechanical stress — the same things that caused the pads or shoes to
    wear out — will eventually cause the brake hardware to fail. The results
    can range from reduced braking efficiency, to premature wear on pads and
    shoes, to complete and unexpected brake failure. Replace the Hardware.
  • No DOT 5 in ABS. Be aware that silicone or DOT 5 is
    not recommended for ABS use, since it often aerates when agitated. DOT 3
    and DOT 4 fluids are mineral based and will absorb moisture over time. If
    this moisture finds its way into the ABS solenoid valves, it can create
    corrosion problems and expensive repair bills.
  • Upgrade to performance. Brake pads and linings are
    available in many different grades and materials. A customer with
    aggressive/sporty driving habits should consider upgraded products that
    better suits their needs. High performance European cars and SUV s will
    benefit from high quality brake linings and components.


  • Audi, BMW, Porsche , and Volkswagen SUVs have higher
    centers of gravity, which is a key reason to replace shocks/ struts.
    Shocks/struts help control vehicle weight transfer (and resistance to
    rollovers) under hard braking and cornering situations.
  • Shocks should be sold in pairs, even if one seems to
    be in good shape. If one side is worn, both shock absorbers should be
    replaced to prevent an uneven ride. Also bushings should be replaced
    whenever shock absorbers are replaced. Struts also should be rebuilt or
    replaced in pairs.


  • Tie-rod ends. When looking up tie-rod ends or drag
    link ends, you may run across left-handed and right-handed versions of the
    same piece. This may refer to the threads where the tie-rod end screws
    into the sleeve or rod, or which side of the vehicle it is on. Many times
    it also is necessary to replace the threaded sleeve that the tie-rod end
    screws into.
  • Be proactive. With labor accounting for the lion’s
    share of the clutch replacement bill, preventive maintenance is essential.
    For example, replacing the concentric slave cylinder (CSC), on vehicles so
    equipped, is cheap insurance against comebacks. The same is true for
    transmission and engine seals, cables and forks, and hydraulic master and
    slave cylinders.


  • Puff of smoke from the exhaust can tell you a lot
    about the car’s engine heath. Blue smoke from the tailpipe means the
    engine oil is being burned. Black smoke means the air-fuel mixture is too
    rich to burn completely. White smoke is steam and is normally visible on a
    cold day; however, it also can indicate an internal engine coolant leak,
    if accompanied by a pungent odor.
  • At the very least, you should provide new clamps
    whenever any portion of the exhaust is replaced, as well as any required
    gaskets and hangers. If the pipe or muffler does not fit the vehicle due
    to previous installation, you will need to have new adapters to go from
    one pipe size to another, or replace all of the system that is affected.
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