Installing a Subframe Mount
Subframe mounts are hard, sturdy, and strong. There is a reason why they are like this: a subframe carries the heavy load of an engine, and its mount supports it while it does its job. This means that a subframe mount is also strong and, more importantly, is installed properly. If you are replacing or installing a new subframe mount, here's a guide on how to do it correctly.
Required skill level: Intermediate
Needed tools and materials
- Subframe mounts
- Hydraulic jack/jack stands
- Bearing puller/installer
- Differential mount
- Tabs for different differential mounting bolts
- Metric tap and die
Easing into the installation
Jack up the car and mount it on the jack stands using the hydraulic jack. Let the subframe drop a bit by loosening the 3 mount bolts.
Secure the frames
Use a pry bar to get the subframe down for 'hand' clearance. Run a threaded rod through the subframe mount. Use washers on the rod, placing them at the top. Afterwards thread 2 nuts at the top of the rod. Leave about half of the thread exposed above the washer. This process helps you to have better control of the rod, and to use a wrench and a ratchet on the upper and lower nut.
Using the rod to remove the mount
Run the threaded rod into the mounting hole. Use your pry bar to create clearance between the subframe and the body. Ensure that the threaded rod is inserted in the mounting hole by taking 2 nuts by hand and increasing the distance between them. Increase the pressure on the subframe using the jack. This will create tension.
Removing the mount and replacing
Tap the side of the subframe mount with a blunt-faced instrument. It will release because of the tension. 'Walk' it all the way until it falls out. Measure the new mount against it, to make sure it is the same size. Afterwards, using the bearing puller/installer, press the new mount into the subframe. Don't forget to install the small rubber mount before everything else.
Jack the subframe until it seats in the unibody. Place cage assembly on the subframe mount. Afterwards, secure it by bolting it down with the three bolts. Repeat on the other side of the car. Finish up by installing the rear differential guard.
Tips and warnings
- Take note of the bolts in the car. If they do not release cleanly, do not attempt to force them.
A Guide to Fixing Your Car’s Subframe Mount
The subframe mount is a steel-sleeved rubber bushing assembly that supports the weight of the subframe in many motor vehicles. These subframe mounts can last as long as the vehicles that they are installed in, but poor maintenance and rough driving environments can cause these mounts to malfunction and break down.
A faulty subframe mount is often best replaced with a new set, but you can try fixing it first and save yourself money in the process. In this guide, we will show you the steps to fixing problematic subframe mounts in your vehicle.
Difficulty level: Moderate
What you'll need:
- Floor jack
- Jack Stand
- Socket set
- Torque wrench
- Flat head screwdriver
- Pry bar (optional)
Step 1: Jack up the car and place jack stands under the lower control arms and the rear axle. Make sure the vehicle is on a stable and level surface when you do this.
Step 2: Disconnect and remove the battery, the battery tray, the windshield washer reservoir, and support braces. Once they are out of the way, you should be able to access the subframe mounts with ease.
Step 3: Support the subframe with a jack and loosen the front and rear mounting bolts. Make sure to work only on one side at a time, as removing bolts on both sides may cause the subframe to go out of alignment.
Tip: For front subframe mounts, block the bolt first from turning and remove the nut from the bottom.
Step 4: Pull out the mounts from the subframe and check the condition of each one. If the mount already appears brittle to the point of crumbling or is flattened to half its original height, it may be better to discard the mount and replace it with a new one. Check the hardware of the mounts as well if they need replacement. If the bolts appear in good condition but are particularly rusty, soak them in a commercial rust dissolving solution for an hour or two and grind the corroded surface with sandpaper.
Step 5: Clean off any dirt and debris on the mounts using a stiff brush and soap mixed with warm water. Wipe it dry with a rag and spray with a silicone based lubricant.
Step 6: Reattach the rear subframe mounts, followed by the center and front mounts. The subframe in most vehicles usually have alignment holes that you can use as reference to align the mount, the subframe, and the body of the car correctly to one another.
Tip: You can use a pry bar or a similar long and sturdy tool to nudge the mount in between the subframe.
Step 7: Once they are properly aligned, tighten the mounting bolts until you feel that they are snug. Do not tighten them beyond that for now.
Step 9: Replace the braces, the windshield washer reservoir, and other components that you have removed earlier.
Step 10: Lower the vehicle gently into the ground and place chocks underneath the wheels to prevent them from moving.
Step 11: Roll underneath your vehicle and tighten the bolts according to manufacturer specifications.