The 1987 Ford Bronco II is a classic SUV that many enthusiasts still cherish today. However, like any vehicle of its age, it can be prone to certain issues, especially with its transmission. Understanding these common problems and their solutions can help you keep your Bronco II running smoothly for years to come. In this article, we’ll dive into the typical transmission troubles you might encounter with a 1987 Ford Bronco II and provide practical advice on how to address them.

Common Transmission Problems in the 1987 Ford Bronco II

When it comes to the 1987 Ford Bronco II transmission, several common issues tend to surface. Recognizing these problems early can save you from more extensive and costly repairs down the road. Here are some of the most frequently reported transmission issues:

Slipping Gears

Slipping gears is a classic symptom of a transmission on its way out. If you notice that your Bronco II struggles to stay in gear, especially when accelerating or climbing hills, this could indicate worn clutches or bands inside the transmission. The transmission might unexpectedly shift into neutral or another gear, leading to a loss of power and potentially dangerous situations, especially at higher speeds.

Causes of Slipping Gears:

• Worn Clutches and Bands: Over time, the friction material on the clutches and bands wears down, reducing their ability to grip and hold the gears in place.
• Low Transmission Fluid: Insufficient fluid levels can cause the transmission to overheat and the internal components to fail prematurely.
• Contaminated Transmission Fluid: Dirty or contaminated fluid can clog valve bodies and passages, leading to poor shifting performance.
• Internal Mechanical Damage: Broken or damaged gears, shafts, or other internal components can also cause slipping.

Solutions for Slipping Gears:

1. Check Transmission Fluid Level and Condition: Start by checking the transmission fluid level using the dipstick. The fluid should be at the appropriate level and have a bright red or pink color. If the fluid is low, add the recommended type of transmission fluid. If the fluid is dark, smells burnt, or contains debris, it's time for a fluid and filter change.
2. Transmission Fluid and Filter Change: Changing the transmission fluid and filter can often resolve minor slipping issues. This process involves draining the old fluid, replacing the filter, and refilling the transmission with fresh fluid. Make sure to use the correct type of fluid specified for your Bronco II.
3. Adjusting Shift Linkages: Sometimes, slipping gears can be caused by misadjusted shift linkages. The shift linkages connect the gear shifter to the transmission, and if they are not properly adjusted, the transmission may not fully engage the selected gear. Adjusting the linkages can improve shifting performance.
4. Professional Inspection: If the above steps don't resolve the slipping issue, it's best to take your Bronco II to a professional mechanic. They can perform a thorough inspection of the transmission to identify the underlying cause of the problem. This may involve removing the transmission pan to inspect the internal components for wear or damage.
5. Transmission Rebuild or Replacement: In severe cases, the transmission may need to be rebuilt or replaced. A rebuild involves disassembling the transmission, replacing worn or damaged parts, and reassembling it. A replacement involves installing a new or remanufactured transmission in place of the old one. Both options can be costly, but they are often necessary to restore proper transmission function.

Rough or Hard Shifting

Rough or hard shifting is another common transmission issue in the 1987 Ford Bronco II. Instead of smooth transitions between gears, you might experience jolts or harsh engagement. This can make driving uncomfortable and may indicate a more serious underlying problem. Hard shifting can occur in both automatic and manual transmissions, although the causes and solutions may differ.

Causes of Rough or Hard Shifting:

• Low Transmission Fluid: As with slipping gears, low transmission fluid can also cause rough shifting. Insufficient fluid levels can lead to inadequate lubrication and hydraulic pressure, making it difficult for the transmission to shift smoothly.
• Contaminated Transmission Fluid: Dirty or contaminated fluid can clog valve bodies and passages, leading to erratic shifting behavior.
• Faulty Valve Body: The valve body is a complex component that controls the flow of transmission fluid to different parts of the transmission. A faulty valve body can cause improper shifting and rough engagement.
• Worn Synchronizers (Manual Transmissions): In manual transmissions, worn synchronizers can make it difficult to shift smoothly between gears. Synchronizers are responsible for matching the speeds of the gears before they engage.
• Clutch Problems (Manual Transmissions): A worn or damaged clutch can also cause rough shifting in manual transmissions. If the clutch is not fully disengaging, it can make it difficult to shift gears smoothly.

Solutions for Rough or Hard Shifting:

1. Check Transmission Fluid Level and Condition: Just like with slipping gears, the first step is to check the transmission fluid level and condition. Make sure the fluid is at the proper level and is clean and free of debris. If the fluid is low, add the recommended type of transmission fluid. If the fluid is dirty or contaminated, a fluid and filter change is in order.
2. Transmission Fluid and Filter Change: Changing the transmission fluid and filter can often improve shifting performance. This will remove any contaminants that may be causing the rough shifting. Be sure to use the correct type of fluid specified for your Bronco II.
3. Adjusting Shift Linkages: Misadjusted shift linkages can also contribute to rough shifting. Make sure the shift linkages are properly adjusted so that the transmission is fully engaging the selected gear.
4. Valve Body Inspection and Repair: If the rough shifting persists after checking the fluid and linkages, the valve body may be the culprit. A professional mechanic can inspect the valve body for damage or wear and recommend repairs or replacement if necessary.
5. Synchronizer Replacement (Manual Transmissions): If you have a manual transmission, worn synchronizers may be causing the rough shifting. Replacing the synchronizers can restore smooth shifting performance.
6. Clutch Replacement (Manual Transmissions): If the clutch is worn or damaged, it may need to be replaced. A new clutch can improve shifting performance and make driving more enjoyable.

Transmission Overheating

Transmission overheating is a serious issue that can lead to significant damage to your 1987 Ford Bronco II's transmission. Excessive heat can break down the transmission fluid, causing it to lose its lubricating properties and leading to increased wear on internal components. Overheating can also damage seals, gaskets, and other parts, resulting in leaks and further complications.

Causes of Transmission Overheating:

• Low Transmission Fluid: Insufficient fluid levels can lead to increased friction and heat buildup inside the transmission.
• Clogged Transmission Cooler: The transmission cooler is responsible for dissipating heat from the transmission fluid. A clogged cooler can restrict the flow of fluid and cause the transmission to overheat.
• Heavy Towing or Hauling: Towing heavy loads or hauling heavy cargo can put extra strain on the transmission, causing it to generate more heat than normal.
• Prolonged Idling: Extended periods of idling, especially in hot weather, can also cause the transmission to overheat.
• Internal Transmission Problems: Internal issues such as worn clutches or bands can generate excessive heat as they slip and struggle to engage.

Solutions for Transmission Overheating:

1. Check Transmission Fluid Level and Condition: As with other transmission problems, the first step is to check the fluid level and condition. Make sure the fluid is at the proper level and is clean and free of debris. If the fluid is low, add the recommended type of transmission fluid. If the fluid is dark or smells burnt, it's time for a fluid and filter change.
2. Inspect and Clean Transmission Cooler: Check the transmission cooler for any signs of damage or blockage. Clean the cooler fins to ensure proper airflow. If the cooler is severely clogged, it may need to be replaced.
3. Install an Auxiliary Transmission Cooler: If you frequently tow heavy loads or haul heavy cargo, consider installing an auxiliary transmission cooler. This will provide additional cooling capacity and help prevent overheating.
4. Avoid Prolonged Idling: Minimize extended periods of idling, especially in hot weather. If you must idle for a long time, try to do so in a shaded area or turn off the engine when possible.
5. Professional Inspection: If the transmission continues to overheat despite these measures, it's best to take your Bronco II to a professional mechanic. They can perform a thorough inspection of the transmission to identify any internal problems that may be causing the overheating.

Unusual Noises

Unusual noises coming from your 1987 Ford Bronco II's transmission can be a sign of various problems. These noises can range from whining and humming to clunking and grinding, and they can often provide valuable clues about the source of the issue. Paying attention to the type of noise, when it occurs, and under what conditions can help you diagnose the problem more accurately.

Types of Transmission Noises and Their Possible Causes:

• Whining Noise: A whining noise that increases with vehicle speed may indicate a problem with the transmission pump or torque converter.
• Humming Noise: A humming noise can be caused by worn bearings inside the transmission.
• Clunking Noise: A clunking noise when shifting gears may indicate worn u-joints, loose shift linkages, or internal transmission damage.
• Grinding Noise: A grinding noise when shifting gears, especially in manual transmissions, may indicate worn synchronizers or damaged gears.
• Rattling Noise: A rattling noise can be caused by loose parts inside the transmission or a worn-out torque converter.

Solutions for Unusual Transmission Noises:

1. Identify the Source of the Noise: Try to pinpoint the exact location and conditions under which the noise occurs. This can help you narrow down the possible causes.
2. Check Transmission Fluid Level and Condition: Low or contaminated transmission fluid can sometimes cause unusual noises. Make sure the fluid is at the proper level and is clean and free of debris.
3. Inspect U-Joints and Shift Linkages: Check the u-joints and shift linkages for any signs of wear or damage. Replace any worn or damaged parts.
4. Professional Inspection: If you can't identify the source of the noise or if the noise persists after checking the fluid, u-joints, and linkages, it's best to take your Bronco II to a professional mechanic. They can perform a thorough inspection of the transmission to diagnose the problem and recommend the appropriate repairs.

No Shifting

No shifting is a critical issue that prevents your 1987 Ford Bronco II from changing gears, leaving you stranded. This problem can stem from a variety of mechanical or electronic failures within the transmission system. Identifying the root cause is essential for effective repair.

Potential Causes for a Transmission Not Shifting:

• Broken Shift Cable or Linkage: The cable or linkage connecting the gear shifter to the transmission might be broken or disconnected.
• Valve Body Issues: A malfunctioning valve body can prevent the transmission from shifting correctly due to improper fluid flow management.
• Solenoid Problems: Faulty solenoids within the transmission can disrupt the hydraulic control necessary for gear changes.
• Internal Damage: Significant internal damage to gears or other components can mechanically prevent the transmission from shifting.
• Electronic Control Unit (ECU) Failure: In some models, a failure in the ECU can disrupt electronic signals needed for shifting.

Troubleshooting Steps for a Transmission That Won’t Shift:

1. Inspect Shift Cable/Linkage: Check the shift cable or linkage for any visible damage or disconnection. Repair or replace as necessary.
2. Check Fluid Levels: Ensure the transmission fluid is at the correct level and in good condition. Low or dirty fluid can inhibit shifting.
3. Scan for Diagnostic Trouble Codes (DTCs): Use an OBD scanner to check for any transmission-related error codes that can point to specific issues.
4. Professional Diagnostic: Due to the complexity of modern transmissions, it’s often best to consult a professional mechanic who can accurately diagnose and repair the problem.

Tips for Maintaining Your 1987 Ford Bronco II Transmission

Maintaining the transmission of your 1987 Ford Bronco II is crucial for ensuring its longevity and optimal performance. Regular maintenance can help prevent many of the common issues discussed above and keep your Bronco II running smoothly for years to come. Here are some essential tips for maintaining your transmission:

Regular Fluid and Filter Changes

Regular fluid and filter changes are perhaps the most important maintenance tasks you can perform for your transmission. Fresh transmission fluid provides proper lubrication, cooling, and hydraulic pressure, while a clean filter prevents contaminants from circulating through the system. Follow the manufacturer's recommended service intervals for fluid and filter changes, or more frequently if you do a lot of heavy towing or off-roading.

Check Fluid Level and Condition Regularly

Checking the fluid level and condition regularly is a simple but effective way to monitor the health of your transmission. Use the dipstick to check the fluid level, and make sure it is at the proper level. Also, inspect the fluid for any signs of contamination, such as a dark color, burnt smell, or the presence of debris. If you notice any of these signs, it's time for a fluid and filter change.

Avoid Harsh Driving Habits

Avoiding harsh driving habits can also help prolong the life of your transmission. This includes things like aggressive acceleration, hard braking, and frequent shifting. These habits can put extra strain on the transmission and cause premature wear on internal components. Smooth and gentle driving will help keep your transmission in good condition.

Address Problems Promptly

Addressing problems promptly is essential for preventing minor issues from turning into major repairs. If you notice any signs of transmission trouble, such as slipping gears, rough shifting, or unusual noises, don't ignore them. Take your Bronco II to a professional mechanic as soon as possible for diagnosis and repair. Delaying repairs can often lead to more extensive and costly problems down the road.

Keep the Transmission Cool

Keeping the transmission cool is also important for preventing overheating. Make sure the transmission cooler is clean and free of debris, and consider installing an auxiliary transmission cooler if you frequently tow heavy loads or haul heavy cargo. Also, avoid prolonged idling, especially in hot weather.

Conclusion

The transmission in your 1987 Ford Bronco II is a vital component that requires proper care and maintenance. By understanding the common problems that can occur and following the tips outlined in this article, you can help keep your transmission running smoothly and reliably for years to come. Regular maintenance, prompt repairs, and careful driving habits are the keys to prolonging the life of your transmission and enjoying your classic Bronco II to the fullest. If you encounter any serious transmission issues, don't hesitate to seek the help of a qualified mechanic to ensure the job is done right.