Differential Unit Problems of BMW Z3

I have a 1998 Z3 m roadster and the trunk welds holding the subframe is failing. This is a commonly documented issues. BMW dealers acknowledge the issue but BMW north America will not fix it. This is a welding/manufacturing defect that can lead to the differential and suspension components in the rear to completely separate.

See all problems of the 1998 BMW Z3 🔎.

Very well known failure, just search for "BMW Z3 subframe failure". It is a design flaw by BMW that affects a lot of Z3's through all model years. Mine started to pop one weld at 88k miles. It can cause the rear alignment to be off, in worst case the trunk floor is torn out and the differential falls to the ground. Clunking from the back while shifting in the first two gears is one indicator this damage is not far away. . Read more...

See all problems of the 1999 BMW Z3 🔎.

The rear differential housing is separating from the subframe of the car, under or near the trunk area. This is a well documented issue with the Z3 series of vehicles. This could be a safety hazard while operating the vehicle if the read differential separates from the subframe, and could cause a hazard to other motorist. This appears to be due to a design flaw. The frame was designed for a 1. 9l engine, and BMW did not redesign the subframe to allow for the larger engines it later sold in the Z3 series of cars. BMW also had this same issue on 3xx series of vehicles, and agreed to repair those cars due to a class action law suite settlement. BMW should be held accountable for the design issue, and acknowledge the safety hazard.

I have subframe damage, in the trunk it's most visible with the carpet out, I can see the spot welds have popped, cracked, broke free, whatever. Thus can cause a massive risk to as if anymore pop the differential could possible tear next the bracket that holds it up.

I purchased a used 1998 BMW Z3 with the 1. 9 liter engine on 10/14/2010 with 90564 miles. In mid November I took the car to a mechanic for a check engine light which was serviced. The mechanic informs me there is a problem with Z3's along with other model BMW's with the way the rear differential is attached. The problem seems to be flexing in the sheet metal where the differential is attached causing failure of the spot welds holding the whole assembly together. He showed me in my trunk where two of the six spot welds had broken. I have researched this on the different BMW forums and BMW is claiming this failure is due to performance modifications or cars that have been taken to a track or autocross. I do not know the previous history of my car but it appeared to have been taken care of. On 6/30/2011 I had the car in the shop again for service work and my mechanic found two more broken welds and some separation in the rear chassis. This car is pretty much un-drivable now due to this condition. I understand there is a couple of companies that make a repair kit for this that will strengthen the trunk area and prevent this from happening again.

On 24jun2011, I swerved from a parallel lane to avoid being sideswiped. No contact was made between vehicles. However, I noticed a noise coming from the rear of the vehicle. The vehile has a manual transmission. I took the vehicle to an auto body repair shop. After examining the vehicle they told me that: the flange/bracket that held the differential in place had a complete hair-line fracture; and, that a substantial number of spot welds holding the body on to the frame had failed. I made contact with the local BMW dealership mcgrath BMW, ocated in westmont, IL and told them of the incident. They stated that they did not undertake body repairs and directed me to a firm which did all types of body and structural repairs and was accredited by BMW. I was given an estimate for the repair of between $5,000-$6,000, and was told that there was no program offered by BMW to share in the cost of the flange/bracket and body repair. I went back to my local body shop and told them to estimate the cost and I also reported the problem to my auto insurance (state farm). An adjuster from state farm reviewed the failures and stated that the condition was one of a problem in manufacture and not covered by my auto insurance. My body shop then gave me an estimate of a not to exceed figure of approximately $2,500. I told them to undertake the repair. The flange/bracket has been replaced and reinforced and the body and frame have since been rewelded at a total cost to me of $1600. Additionally, I spent an additional $100 for a alignment (firestone of countryside, IL) the local body shop is douglas auto body, 4015 eberly avenue, brookfield, IL (708) 485-7774 - they are a body and structural repair shop approved by state farm insurance. This vehicle has been used by me as a street vehicle and not for racing or track use of any kind. The failures seem to be a mfg. Design flaw.

See all problems of the 2000 BMW Z3 🔎.

The contact owns a 1999 BMW Z3. The contact stated that the vehicle was increasingly hard to control and the vehicle was taken to a local repair facility for an alignment. The mechanic advised the contact that the rear differential had failed and was causing the wheels to fracture from the sub frame. The mechanic also advised the contact of the recall associated with NHTSA campaign id number: 99v272000 (power train: driveline: differential unit). The manufacturer was contacted and the contact was advised to have the vehicle towed to the dealer. The vehicle was towed and the contact was awaiting diagnosis and repairs. The failure and current mileage was 105,000.

At 86k miles on my 1998 BMW Z3, the thin sheet metal bracket holding the rear differential up in place welded to the chassis split in half causing the rear end to hang. This is the second time it has happened, also at 93,500 miles, just 8 months later. The clutch is still original and the car has never been abused, or raced. I always baby the car because gas is so expensive, and this seems to be a problem with alot of other Z3's that I have seen online. This is clearly a manufacturing flaw. BMW claims the car must have had some rear end impact, even though this is clearly not the case. I would like to see them replace this part with thicker, or stronger metal as it can be a very serious problem if the differential falls out at high speeds.

Z3 subframe problem. Possible detachment of differential from car.

I purchased my car from rose imports in vallejo, CA. On 08-22-2006. Approximately 1 month later, I started to hear a noise from the rear. I would hear it occasionally. On 10-10-2006, I was driving home on I-80 and as I was driving, suddenly I hear a loud "pop". I pull over and did a visual check but found nothing I could see so I continued to drive home and heard metal sounds coming from the back. The next day while driving to work, I continued to hear the sound and when I returned home, me and a friend lifted the car and that's when I discovered the snap or break in the differential support bracket. It has completely separated from the differential. The dealer where I purchased the car told me good luck. They're not going to do anything since it passed their safety inspection. I called my local BMW dealer and spoke to the service dept. And they told me it was nothing they can or will do because it's 86k miles and out of warranty. Now I'm stuck with a car I just purchased and have a major bill 2 months later.

The vehicle was parked when the driver noticed that the differential was hanging from underneath the vehicle. The driver had the vehicle towed to the dealer. The mechanic informed the driver that the rear trunk sub frame needed replacement and welding.

While on a trip I noticed an odd knocking noise from the left rear of vehicle during accelleration while in 1st gear. Upon further inspection I found the car's sub frame in the area supporting the rear differential mount fractured and breaking away from the vehicle. The noise was due to the emergency brake cable that had popped out of its retention clip, due to the physical movement of the supporting material around it. If this had not happened, I would not have noticed the failure until the mount had broken away entirely. Since this mounts the rear axle of the vehicle, it is possible for this to fail at high speed causing loss of control of the vehicle with a high potential of accident and/or injury. I am having this repaired immediately before driving the vehicle any further. This problem appears to be common to the "m" version and many of the straight 6 cylinder version of this vehicle. My version is a 2. 8 liter standard roadster. It is likely a stress failure due to the higher torque of these engines. To correct this failure the damaged material needs to be rewelded and reinforced with additional support.

I own a 1999 BMW Z3 2. 3 roadster. The differential mount has torn away from the underbody of the car where it was welded when designed. This is the third complaint about this particular defect on this website but there are several more on bimmerfest. Com. BMW na should be made aware of this design flaw and forced to do a recall on all cars they made with this flaw. I will seek all necessary legal action to hold them accountable. You don't pay $40,000 for a car they claim as the best car on the road to have a major safety issue like this exist.

Niello BMW of sacramento checked my Z3 2000 for traction control light is on advise, and some fluttering noise came out during acceleration. They found out that there's metal shavings in the differential. They repaired it and replaced it with new one as what they advised to me, plus they replaced thr brake pads, rotors, sensor drive belts, cover air bag and that cost $3200. 18 which I paid. I questioned them if that's still be covered by the warranty since I bought that car in may 1999, and they said," no it's not under warranty. " so I paid the whole amount of $3200. 18. So I drove my car and in a matter of days the car broke again, stopping in the middle of freeway, and that time I heard some fluttering noise again underneath, which scared me. So I immediately called some help and took my car to niello BMW in sacramento for repair and it them a week to repair my car. After it was being repaired I traded it in with Lexus RX 330 in roseville since I'm scared already driving BMW and don't trust that car again.

The differential mount on my 1999 BMW Z3 coupe 2. 8 has cracked. Should this mount fail completely, I fear that serious harm may come to another driver, passenger or myself.

While driving 50-60 mph wheels locked up, causing vehicle to veer from side to side, finally spun around. Vehicle was towed to dealership, it was determined that differential had locked up and needed to be replaced.

See all problems of the 1997 BMW Z3 🔎.

While traveling approximately 40 mph rear differential unit locked up, causing right/ rear tire to stop spinning. Dealership is examining vehicle and making all necessary repairs. Please provide any additional information / documentation.

See all problems of the 1996 BMW Z3 🔎.