1. What is the history of the BMW 540i through the E34?
The third generation 5 Series started arriving in late 1987. Totally redesigned, very similar to the 7 series, the new body was stiffer, offered less wind resistance, improved upon the front/rear aerodynamics and improved crosswind stability. The cars were lighter and offered more interior room.
Introduced with five basic models, by the end of production taking into account engine combinations, 18 types of the E34 were available with a power range of 113 horsepower to 315 horsepower. They arrived in the US in 1988 as the 525i and 535i, which were joined by the M5 in 1990.
In 1991, the 5 Series diesel made a real leap forward with the introduction of a turbocharged 143 horsepower engine. In 1992, a dramatic increase in performance was seen with the introduction of the eight-cylinder models. The 530i with 218 horsepower (215 in the US) and 540i (286 hp, 282 in the US) replaced the 535i and 530i.
The E34 generation finished production with 1,333,438 examples. As a sendoff BMW North America requested a “BMW Exclusive” edition of the 540i be produced to satisfy demand created by departure of the M5 in 1993 and to hold up “end of model line” sales. Other examples of “BMW Exclusive” models produced this way include the 1994 325i M-Sport, 1994 318ti ClubSport, and the 1995 M3 Lightweight.
To create a special car for the US market, the engineers at newly created BMW Motorsport Gmbh (BMW M) division, looked to the mighty 1995 M5 for inspiration. The Europe only 3.8L M5 provided brakes, steering, suspension, bodywork, and other bits to the 282HP V8 engine retaining it’s US certification. Another newly created BMW Division, BMW Individual, carried out actual production of the US 540i M-Sport allowing it to be build on the same Dingolfing assembly line as other 540s. This differs from most previous M cars (including the 1995 M5) which were pulled from the line as a rolling chassis and finished by hand at the Motorsport facility in Garching.
2. How many US 540i M-Sports were produced?
Total production was 200 cars, 135 were 6-Speeds and 65 Automatics.
As of 2018, there is some debate around the total number of M-Sports made. Apparently there were 5 pre-production cars built and it’s not clear whether these are counted in the 200 number or not.
3. What Options made up the Sport Package?
The Sport Package (Options 812/813) listed for $8360 and included
- M5 High Performance Brakes (315X28 Front and 302X20 Rear)
- M5 EDC III Adaptive Suspension with control switch for Sport and Comfort Settings
- Self-leveling Suspension
- 17" M5/850 CSi Forged Alloy two-piece Turbine II Wheels (8 x 17" frt. and rr.) with 235/45 x 17" High Performance Summer Tires
- M5 Servotronic Steering and M Leather Sports Steering Wheel with Air Bag
- Not documented was the increase in speed limiter from 129 to 155 Mph
The following M5 exterior body parts are painted in the body colors:
- Front Spoiler
- Side Sills
- Rear Apron
- Sport Seats (also for the 540iA)
- Illuminated M5 leather Shift Knob (Manual)
- 850 Shift Knob (Automatic)
- Wood trim in high gloss Burl Walnut
- Door sill cover with "M" logo
Upholstery: "Montana" Leather available in the following colors:
- Light Silvergray
4. What Options were offered for the 540i?
- 209* - Limited Slip Differential
- 214* - ASC+T
- 494 - Heated Front Seats
- 812 - Sport Package- 6 Speed Manual
- 813 - Sport Package - Automatic
- Note: Limited Slip or ASC+T are recommended together
5. How can I tell an M-Sport from a regular 540i?
See this page: Is it a REAL 540i M-Sport?
6. Where can I find maintenance information??
There are a number of excellent web sites with E34 maintenance information. The best are:
- The 1995 BMW 540i M-Sport Discussion Group on Facebook!
7. What happens if the check engine light comes on?
The 540i Sport is equipped with a diagnostic system to aid in troubleshooting. Should your check engine light come on you can easily determine exactly what failure has occurred.
Reading the Check Engine Light
- Sit in the driver’s seat.
- Turn the ignition switch to the On position, but do not start the car.
- Immediately depress the accelerator pedal fully and release fully 5 times in quick succession.
- Wait a few of seconds. The Check Engine light will flash once, then begin to blink. Each codes is comprised of 4 digits. The number of blinks corresponds to the fault code. For example, ON, pause, ON ON, pause, ON ON, pause, ON ON, off would be a 1222.
- Each four-digit code will be flashed sequentially.
When the codes start to repeat, all stored codes have been displayed. 6. Turn ignition switch Off. 5.1.2 Fault Codes Bosch Motronic v3.3 are listed in Appendix 8.1
8. When should I replace the O2 Sensors?
The 540i Sport is equipped with a dual exhaust system with dual Oxygen (O2) Sensors. These sensors are critical to engine performance and could be replaced every 50k miles. There are three types of replacement sensor available. The easiest and most expensive is to go the dealer and order the factory part for about $300. For about $230 you can order a Bosch replacement part from the Ultimate Garage. The least expensive solution, the Bosch universal sensor is available from the same source. The Universal sensor will require you to reuse the connector from your old sensor and splice the wires.
9. My Catalytic Converters are rattling, what do I do?
540i catalytic converters are prone to rattling as the clutch is released in 1st gear. This is due to the internal ceramic matrix breaking due to age. BMW Factory Cats are very expensive $1800/Pair. Aftermarket replacements are available from DEC for about $600/Pair.
10. What should I worry about in the Lubrication System
Oil Pump Bolts Many (all?) M60 V8s as installed in the 540i suffer from loose oil pump bolts. These bolts hold the oil pump together and to the bottom of the engine. With age these bolts become loose and fall out into the oil pan. If you own one of these car have them checked. 5.4.2 Oil Leaks M60 V8s commonly leak oil from around the Cam and Timing Cover gaskets. If not corrected, engine mounts can fail from prolonged exposure to oil.
11. What about the Hydraulic System?
The 540i Sport is equipped with a complex hydraulic system used by both Power Steering and the Self-Leveling rear suspension. A common reservoir is used and only Pentosin CHF11S (which comes in cans with RED caps only). At the bottom of the hydraulic reservoir is a mesh filter that should be cleaned every couple of years.
12. When should I replace the Microfilter
The Microfilter in the HVAC of all 540s is scheduled to be replaced every 15k miles. Replacement improves air-flow, heater-A/C Performance, and may extend the life of the heater fan resistor pack.
13. What Modifications/Upgrades are available?
- Jim “Landshark” Conforti offers a replacement ECU chip claiming to offer an additional 19HP and 33ft/lbs of torque.
- Gearing Lower (numerically higher) rear differentials are available for the 540. Apparently the Limited Slip diff from an E32 750il is a bolt-in swap available in 3.15 (for 6-speed) and 3.64 (Auto) ratios. Dinan and Korman offer rebuilt performance units in the same ratios.
- Differential Quafe Engineering offers a aftermarket differential for the 540 based on their patented design. Dinan Engineering offers a choice of gearing options and can rebuild the factory diff for increased locking force.
14. What about wheels and tires?
Original sizes are 17X8 ET20 or 17X8 ET20/ 17X9 ET 22 wheels and 235/45-17 tires. The E34 chassis can fit either 17" or 18" wheels with widths between 8 and 9.5 inches. 8.5" is probably the max front width and 9.5 is the max rear width when using correct offset wheels. 6.3.1 17" wheels I have seen 17X9" wheels front and rear with 245/40-17s. 245s are a bit narrow for 9" rims but it’s probably the largest front tire that will fit a 17" rim. I have actually seen 17X10s and 275/40-17 on an 91 M5 but it had large fender flares.
The maximum practical 17" tires are probably 245/40-17 for front tires and 265/40-17s for rears. 6.3.2 18" wheels 18" wheels are an easy fit on a 540. The Europe only 1995 M5s were equipped with 18X8 ET20/18X9 ET22 M-Parallel wheels (much like the US 740i Sport). This is a popular upgrade for 540s.
The maximum practical 18" tires are probably 245/40-18 for front tires and 275/35-18s for rears.
15. What Brake Upgrades are there?
There are many aftermarket brake kits for the 540i Sport. 6.5.1 Brembo Brembo offers a "Grand Turismo" kit using 332X32 rotors available as cross-drilled one piece or cross drilled/slotted two piece rotors with aluminum center hats. 6.5.2 Dinan Engineering Dinan offers an upgrade for both front and rear brakes to Euro 1995 M5 Spec using the 345x32mm floating rotors, 4-piston calipers with M Logo in front and 328x20mm fixed rear rotors with single piston calipers in the rear. This kit fits in the stock 17" wheels. 6.5.3 Movit The Ultimate Garage is the US rep for the German Movit brake kit. These packages are based on Porsche "Big Red" and "MonoBlock" brake systems. Front Rotors of 322x32, 330x34, and 380x32mm and rears of 299x24 and 322x28mm are available. These kits require 18" or larger wheels and unusual offsets.
16. What Short Shift Kit Can I get?
UUC offers a short shift kit and Evo bushing for the 6-speed equipped 540i Sport.
17. Are the Clutch Upgrades Available?
CenterForce will take a new factory clutch and modify it to handle over 500hp. They replace the friction material with a Kevlar based material and add their trademark counterweight system to increase clamping force.
18. What about Forced Induction?
Dinan Engineering offered a bolt-on supercharger kit using the Powerdyne supercharger that claims of offer 400+ HP and is passes smog testing in California. ESS Tuning in Norway offered a 6PSI Supercharger kit also using the Powerdyne unit claiming to produce 410HP for less than $5k and is NOT Smog legal in CA.
19. What suspension upgrades are possible?
The 540i Sport shares its "Double Pivot" McPherson strut front suspension and track link semi trailing arm rear suspension with most other E-34 cars. The 540i Sports are also equipped with the hydraulic "Self-leveling" feature found on E34 M5s.
Suspension Packages Dinan and Korman both offer complete suspension packages for E34s and 540i Sports specifically. Korman in fact offers a RoadSport kit for comfortable street use and a ClubSport kit for more track-oriented use. These include Springs/shocks/bars/HD thrust bushings/Decamber plates and yield a well-balanced car that is safe and fun to drive in all conditions.
Anti-Sway Bars Springs Springs are available from a number of manufacturers including Dinan, Korman, Eibach H&R and InTrax. Actual spring rates are not available from these vendors.
Since the 540i Sports are all equipped with EDC, the decision to replace the EDC shocks with aftermarket units should not be taken lightly.
However, with replacement front EDC shocks costing over $2,300 each, it can be a difficult investment. Koni and Bilstein offer performance shocks for the E34 Chassis. Bilstein offers both Heavy Duty and Sport shocks. These are much less expensive that the EDC shocks Anti Sway Bars Stock sizes for the 540i sport are 25mm front and 18mm rear. There are a number of interesting bars available from BMW including a stiffer 25mm front bar and 20mm rear bar from the 3.8L M5 Touring. These parts are less expensive that many aftermarket parts. Both Eibach and Suspension Techniques offer larger bars for the E-34. Eibachs bars are 26mm Front and 13mm Rear and ST bars are 27/19mm. Dinan also offers a set of bars in 25mm/19mm as part of their suspension system.
Bushings/spacers/Etc Decamber plates bolt between the top of the strut assembly and the chassis and are used to increase the static negative camber of the front wheels. This will increase turn-in response and cornering force at the cost of increase front tire wear. Two types are available fixed and adjustable. Dinan, Korman, and Turner Motorsports all sell fixed decamber plates for the E-34. K-Mac and Ground Control sell adjustable plates. BMW Crash Repair Bushings BMW offers a modified version of the bushing at the top of the front strut. These bushings are off center and allow 1/2 degree of camber adjustment depending on how they are installed. These can be combined with fixed decamber plates for maximum negative camber.
Thrust Arm Bushings: Many older E34s develop a front-end shake at 50-60Mph. This is usually caused by worn thrust bushings. There are upgraded replacement parts available from the E32 7 Series. BMP offers a much harder urethane replacement part as well. Adjustable Anti-sway bar links These connect the anti-sway bar to the chassis. Adjustability can be used to improve lateral weight distribution by compensating for the preload caused by the anti-sway bars.
Rear Camber/Toe Adjustability: Dinan and Korman offer weld-in eccentric adjusters to change rear toe and camber.
20. Who Helped make this FAQ?
- Harry Yamada
- David Chen
- Kevin To
- Charlie Kindel
- Bret Anderson
- Filippo Morelli
- Ben Liaw
- Gary Bossert
- Jim Conforti
- Steve Dinan