Dana35 rear differential pinion bearing is shot and not sure if it can be pulled through the hole for the drive shaft
Took a side impact after which a wobble sound started coming from my rear end. I replaced Right side axle shaft and drum backing plate, shoes, springs and drums, but noise still there. Mechanic said it's the pinion bearing. There has always been a boom from the rear end when I put the car in reverse which corroborates this? So is it likely to be the outer pinion bearing by the driveshaft or the inner one behind the spider gears? Can pinion bearing by driveline be pulled through the axle hole? or would it be necessary to take apart differential and gears either way (inner pinion bearing
Experienced mechanics share their insights in answering this question :
You have two pinion shaft bearings. The one that can be replaced by removing the driveshaft and flange on the rear end. You remove the seal and the bearing can be removed. The bearing race cannot be replaced this way if it is damaged. You have to disassemble the rear end and remove pinion shaft to knock out the race, and then you might as well replace the inner pinion bearing and race. The carrier would need to be removed for access and then you have access to the carrier bearings. The two outer axle bearings and seals should then be replaced, or you could replace the complete rear end. If you would like to have this looked at, an expert technician from YourMechanic can come from your location to give your car a comprehensive inspection and advise you on the correct repair.
How to Identify and Fix Common car Problems ?
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Pinion bearings are designed to reduce friction in the direction of desirable movement, increasing efficiency. In drive differentials, pinion bearings help the smallest gears in the differential work smoothly.
Pinion bearing preload is a critical step in the differential overhaul process because if you get too heavy handed you have to backtrack and start over. Further, getting this procedure right sets the stage for each following step of reassembly.
Maintains Proper Gear Mesh
A slight preload bearing setting assures that proper gear tooth contact is maintained between the pinion and ring gear. This minimizes gear wear and extends the tooth life of both gears.
Rotate the pinion with an inch/lbs. torque wrench. The rotational drag should be 20-25 in/lbs (if re-assembling a support with used bearings the rotational drag can be 10-15 in/lbs). If the rotational drag is too low step up the pinion nut torque in 10 ft/lbs increments and re-check the drag.
The pinion gear is made of case carburized steel with low nickel and chromium content and it also has undergone extensive corrosion due to an environmental problem.
Worn pinion bearings can cause whirring noises at all speeds, under deceleration and/or acceleration. Pinion bearings tend to whir, rather than rumble, because the pinion is turning several times faster (depending on gear ratio) than the carrier.
The torque on the pinion is simply the tangential force (force on the rack) multiplied by the pinion radius. Remember to divide the pinion diameter by 2 to get the radius, and by 1000 to convert from mm to m (or by 12 to convert from inches to feet).
Proper bearing preload on the ring and pinion gear set prevents the gears from moving vertically, horizontally, or diagonally as they rotate. Improper bearing preloading allows the gears to push away from each other as you accelerate your vehicle and pull together as your vehicle decelerates.
First, it`s important to know that a preload is required for angular contact bearings. This is because of the bearing design; it needs constant contact to happen between the balls and raceway. This constant contact is achieved through a bearing preload.
The slope of the transmission output shaft and pinion shaft should be in the same direction. They should also be within ½° of each other to avoid driveline vibration. The operating angle of the u-joint between the transmission and the fixed driveshaft should be between ½° and 1-1/2°.
A simple rule for troubleshooting bearing temperatures: No more than 180 degrees Fahrenheit (82 degrees Celsius) on the housing. The bearing outer ring can be up to 20°F (11°C) hotter than the housing.
Making Pinion Harder than Gear to Equalize Wear
The harder pinion teeth correct the errors in the gear teeth to some extent by the initial wear and then seem to burnish the teeth of the gear and increase its ability to withstand wear by the greater hardness due to the cold-working of the surface.
Make sure the matchmarks are aligned. Torque the steering wheel nut to 29-36 ft. lbs. (40-49 Nm).
If it`s a Dana 35 you want the rotational resistance around 16-20 in/lbs.
Carbon-steel alloys are used for almost all types of gearing because they are easy to machine, they have good wear resistance, they can be hardened, they are widely available, and they are relatively inexpensive.
Pinions can be either spur or helical type gears, and be either the driving or driven gear, depending on the application.
According to a recent study, up to 80 percent of bearing failures are caused by improper lubrication. This includes insufficient lubrication, use of improper lubricants or excessive temperatures that degrade the lubricant.
A “whirring” sound generated by unloading via deceleration from most any regular road speed can likely be traced to pinion bearing failure or poor pinion bearing preload. This malady is often diagnosed as a bad ring and pinion gear.
How long does a wheel bearing last? Wheel bearings have an average lifespan of 136,000 to 160,000 km (approximately 85,000 to 100,000 miles).
Planetary bearings
Life expectancy is about 10 years before failures typically set in, although this can vary depending on the make and model of the gearbox.
You can test this by gently swaying your car while driving slowly. If the noise lessens when you sway right, then the damaged bearing is likely on a left wheel bearing. If it lessens when you sway left, a right wheel bearing is likely broken.
Standard bearings – commonly used bearing types for gearbox applications: Cylindrical roller bearings. Spherical roller bearings.
You can increase or decrease a gear`s torque (turning force) by changing the number of rotations.
The gear ratio expresses the ratio of the output torque to the input torque. Thus, we can multiply the torque supplied at the motor shaft (the input) by the gear ratio to find the torque at the wheel axle (the output). Transmitting power through a series of gears can also affect rotational speed.
Relevant Questions and Answers :
the most relevant questions and answers related to your specific issue
Dana35 rear differential pinion bearing is shot and not sure if it can be pulled through the hole for the drive shaft
ANSWER : You have two pinion shaft bearings. The one that can be replaced by removing the driveshaft and flange on the rear end. You remove the seal and the bearing can be removed. The bearing race cannot be replaced this way if it is damaged. You have to disassemble the rear end and remove pinion shaft to knock out the race, and then you might as well replace the inner pinion bearing and race. The carrier would need to be removed for access and then you have access to the carrier bearings. The two outer axle bearings and seals should then be replaced, or you could replace the complete rear end. If you would like to have this looked at, an expert technician from YourMechanic can come from your location to give your car a comprehensive inspection and advise you on the correct repair.
Leaking fluid in front of pumpkin rear axle where drive shaft connects to get. Not sure if i have a bad rear pinion seal
ANSWER : With the age of the vehicle, a worn / failed pinion seal is the most likely cause. Inspect the pumpkin and cover for any damage. If it is apparent that the pinion seal is leaking, make sure the pinion bearing is inspected for excessive play. A worn bearing can eat through a new seal quickly. Have a certified technician inspect the axle and if found to be the cause, replace the pinion seal. Have it done as soon as possible. At the same time, have the axle seals inspected as well. Low gear oil level in the axle will damage gears and bearings in no time.
Can front wheel drive car engine power rear wheel drive
ANSWER : Anything is possible with enough engineering. The changes you are looking at would take major structural changes and would definitely not be an easy job. You could possibly consult a manufacturing engineer to get more details on how this could actually be carried out and whether it would be feasible.
I have a Chrys 300, when I turn it on and put it into drive I hear a grinding noise. I think it’s the drive shaft or differential.
ANSWER : Billing question sent to CS for the cost to repair the driveshaft or differential from making a grinding noise.
Rear pinion has a lot of play in it.
ANSWER : The pinion engages with a ring gear and the other end of the pinion is supported on a tapered roller bearing. If there is any radial play in the pinion itself, there is a problem with the bearing and/or the engagement with the ring gear. If indeed there is an internal mechanical breakage or bearing fault, the rear axle will have to be completely disassembled. Re-assembly requires careful attention to backlash, preload, bearing and shim adjustments and you need a bearing press if you are replacing the bearing. Before doing anything, and to simply confirm that disassembly will be required, you should request a noise diagnostic. If it is determined that the axle will have to be disassembled and repaired, in some locales certified Mechanics dispatched by YourMechanic are equipped for such major on location repairs so you should inquire based on your locale.
I was told I need my rear bearing replaced. I was also told that their are metal shavings in the rear differential.
ANSWER : Hi there. Unfortunately, rear main seal replacement is not among our service offerings. This job is best completed through a machine shop with the correct access to the right tools and shop equipment that makes this job much easier to complete.
How do I remove/replace the driveshaft center support bearing from the shaft?
ANSWER : Hey there. In order to replace the center support bearing you will need to remove the rear drive shaft and then drop the center support bearing and front shaft. The support bearing will need to be pressed off and then new one pressed on to the shaft. The vehicle may not be able to be driven to a repair location without damaging transmission tail shaft. Your best bet here may be to have a mobile mechanic come to you to replace the center support bearing for you.
I hear a rattling noise in the back of my car.I was told I need rear struts not sure which parts
ANSWER : Hi there. I would strongly recommend having a professional mechanic accurately diagnose the issue you’re having if you are going to have a private, non-Mercedes Benz certified mechanic complete these repairs. By having one of our mobile mechanics come to your location and completing a car is making a noise inspection, they will be able to pinpoint the source of your noise and recommend the right repairs.
