Lexus RX350 Transmission Problems – Why Do They Occur?

The present Lexus RX350 traces its history in 2006 making it one of the most resilient products of Toyota's luxury division. It comes from the RX family of luxury vehicles going back to 1997. Aside from the warm welcome of every RX 350 model in the market over the years, none other than JD Power has given it favorable reviews in terms of quality and reliability.

Lexus RX350 automatic transmissions highlights

• Average lifespan:170,000-200,000 miles
• Reliability Score:High
• Prone to minor issues:No
• Price for repair after failure:$1,600-$2,500
• Price for replacement:$5,000-$7,000
• Availability of parts:Average
• Common problems:lots of glitches and electronic problems, high-mileage issues, poor-maintenance failures, sudden limp mode.

Top Transmission Problems in the Lexus RX 350

According to experiences of owners and reports, the most common transmission-related issues in the luxury SUV are the following:

• Slippage
• Leaks
• Overheating

These are fairly common as with every other vehicle due to the effects of regular wear and tear as they age, but there have been claims that these may occur even when the unit is not even half a decade old. The reasons why they happen are up for debate as one side blames Toyota's engineering for them while the other points to lack of maintenance and bad driving habits on the part of the users.

Symptoms, Causes, and Solutions

Regardless of the reason, this part includes ways for you to determine the symptoms of the issues plus ways on how you can diagnose their possible sources and solutions for each.

1. Slippage

Transmission slippage is when the transmission doesn't properly engage, causing the car to jerk or lurch forward. This can be caused by factors such as low transmission fluid levels or worn-out gears.

• Low Transmission Fluid

The first step in diagnosing the cause of transmission slippage is to check the level of fluid in the transmission system. If the level is low, topping it off may resolve the issue.

To check the fluid level in your Lexus transmission, locate the dipstick and remove it. Wipe the dipstick clean with a cloth, then reinsert it into the transmission. Remove the dipstick again and check the level of fluid against the markings on the stick. If the level is low, add more oil to the transmission using a funnel.

The transmission reservoir is normally located beneath the hood on the right-hand side of the engine if you are facing it. If you are still unsure about it, you can have your mechanic do it for you.

The cost for transmission fluid change depends on the brand of the fluid you are using and the prevailing rates in your location but it should start somewhere between $150 and $350 including labor. Meanwhile, a DIY will cut you back to between $50 and $100.

• Worn Gears

If the lubricant is within the recommended level yet you are still having problems with it, other factors may be triggering them. Another likely cause is worn-out gears. If the gears are worn out, they will not be able to properly engage, which will cause the car to jerk or lurch forward. If this is the case, the gears will need to be replaced.

Aside from slippage, an alternative way to check for worn-out gears is to pay attention to a whining noise while the car is in motion. If you hear a whining noise, it may be an indication that the gears are wearing out.

While the application of transmission fluid can be easily done on your part, this solution definitely involves plenty of work and it requires utmost familiarity with the ins and outs of the mechanical parts of your auto. Add to that the weight of the transmission system, which can hardly be carried by a single person. Therefore, we strongly recommend hiring a mechanic to do this for you.

The first step in replacing the worn transmission gear is to place the SUV on an elevated platform and its fluids should be drained. Then, the transmission cover has to be removed. To do this, the bolts that hold the cover in place have to be loosened using a socket wrench. Once the bolts are loose, the cover has to be detached and set aside.

Next, the transmission gear should be located and removed using a ratchet and socket. After that, the replacement part will be positioned in place and installed by reversing the steps taken to remove the old gear. This is also where the mechanic will make sure that all of the parts are properly aligned before tightening them down.

Once everything is affixed, the transmission cover is put back in place and all the bolts are reattached. They will be tightened until they are within the required torque.

Finally, the transmission will be refilled with the recommended fluid and checked for leaks. If neither of these solutions resolves the problem, it may be a sign that there is something else wrong with the transmission and it will need to be diagnosed further.

The price for remanufacturing the transmission of the Lexus RX 350 is estimated to start at $1,300 while a replacement transmission will set you back $4,500 or even more, depending on a lot of factors. Both options are expensive but if you are certain that the system is already malfunctioning, then this will definitely be a smart decision on your part because it will absolutely save you a lot of troubles along the way and it's the best way to guarantee your safety while using your auto.

2. Leaks

If you suspect that your Lexus RX 350 is leaking transmission fluid, there are a few ways to confirm the leak and diagnose its cause. First, check the area around the transmission for any wetness or staining. If you see any residue, use a clean cloth to wipe it away and then check again after the car has been driven for a while. If the leak is coming from the transmission itself, you may be able to see it dripping from the bottom of the car.

• Cracked Transmission Case

Once you've confirmed that there is a leak, the next step is to determine what is causing it. One common cause of leaks is a crack or hole in the transmission case. The process to repair it may involve replacing the entire case, so it is important to consult with a qualified mechanic to get an accurate estimate of the cost and time required for the repair, but it should drive you back around $2,500 to $2,800, including labor.

• Bad Seal or Gasket

Another common cause of leaks is a bad seal or gasket. This will usually need to be replaced. If the transmission fluid level is low, it may be due to a simple leak or it could be because the transmission is not shifting properly, which can cause the fluid to overheat and break down.

If you have confirmed that there is a transmission fluid leak, the best solution is to take your car to a qualified mechanic and have them fix the problem, which should cost you between $150 to $600 depending on the severity of the issue. They will be able to determine the cause of the leak and make the replacement of the necessary parts.

• Damaged Transmission System

The worst thing that could trigger the issue is a damaged transmission system. As mentioned in the previous item, repairs could start at $1,300 while a new replacement can go over $4,500.

3. Overheating

Now, this is the worst that could happen to your RX 350 as this may no longer be just confined to a transmission problem. One way to tell if your transmission is overheating is by the color of the fluid. If the fluid is dark brown or black, it may be an indication that the transmission is overheating. Another symptom of an overheating transmission is slipping gears. If you notice that your car is having trouble shifting gears, it could be a sign that the transmission is getting too hot.

• Lack or Poor Fluid Quality

If you think your transmission may be overheating, there are a few things you can do to fix the problem. First, check the fluid level and make sure it is topped off. If the fluid is low, it could be causing the transmission to overheat. You should also check the condition of the fluid. If it is dirty or burnt, it needs to be flushed and replaced for around $150 to $350.

• Coolant System Problem

If the fluid levels and quality are good, the next step is to check the cooling system. Make sure there is adequate airflow through the radiator and that the cooling fans are working properly. If the cooling system is not working properly, it can cause the transmission to overheat.

For a simple coolant change, you may only spend somewhere between $270 and $320. These can go up if you are facing damage in the system itself.

• Transmission System Fault

Once more, a damaged transmission could be in play here. If you're lucky enough to get away with transmission system repairs, it will still cost you around $1,300. However, if it's a replacement of the entire system, costs may easily balloon starting at $4,500.

Conclusion

Whether you are looking to buy a Lexus RX 350 or you already own one, we hope that you will find all the information provided here quite handy in preparing you for the most common transmission problems found in the unit should you end up encountering any of them.