How to Remove a Subframe
by Don BowmanThe subframe on a vehicle supports everything on the vehicle from the engine and transmission, the lower control arms, the rack and pinion and the sway bar. All instructions must be followed with no exceptions to prevent serious accidents. It is not an uncommon procedure, but everything must be supported when the supporting frame is removed.
Step 1
Disconnect the negative battery cable with a wrench. Raise and support the vehicle on all four corners with the jack stands. Set the jack stands up as high as they will go. Make sure to support the front of the vehicle securely on the body.
Step 2
Attach the engine support stand to the fender wells, making sure that it is secure and will not slip. Attach the chains to the front and rear of engine. Draw the chains up where there is little slack. Move the center of gravity bar toward the front of the engine slightly to make up for the weight of the transaxle. The transaxle usually has an upper mount, but it is not good to have all the weight hanging from it.
Step 3
Remove the wheels using the ½-inch air gun and socket. Remove the cotter pin from the ball joint stud using the wire cutters. Remove the nut with a wrench. Install the ball joint separator tool in between the spindle and the lower control arm and hit the tool with the hammer until the ball joint pops loose from its tapered hole in the spindle. Lift the spindle off of the ball joint stud and let it hang. Do this to both sides.
Step 4
Remove all the clamps for the transmission lines that are attached to the subframe. Use a 3/8-inch drive socket and ratchet to remove the clamps. Move the lines out of the way so they don't interfere with the subframe removal. Check carefully and remove everything attached to the subframe in the way of lines or wires.
Step 5
Remove all motor mounts that are attached to the subframe. Use the floor jack to slightly take some of the weight off to get the bolts out. There is usually one low by the radiator attached to the transmission and another on the other side close to the firewall. Use the 3/8-inch drive sockets and ratchet for this process.
Step 6
Remove the rack and steering bolts with a 3/8-inch drive socket and ratchet. The rack and pinion is going to stay in, but needs to be released from the subframe. Take out the four large bolts going through the brackets holding in to the frame.
Step 7
Attach a security chain around the transmission and the crossbar and make it tight as possible. Secure with a bolt and nut. This is not mandatory but good insurance for the "just in case" scenario; you'll have a big mess if something slips and the engine falls out on the ground.
Step 8
Remove the subframe with the ½-inch air gun and socket by removing one bolt at a time. As soon as the bolt is out, thread it back in by hand six or seven threads. Go to the next one and so on to all four or six (depending on the vehicle) bolts. Have the helpers take a side and lift up on the now lowered subframe and see if it is loose of all items. Remove anything that may have been missed. Have one person remove the bolts in the subframe as the other two helpers support the frame. Lower the frame and remove it from underneath the vehicle.
Things You'll Need
- Set of ½-inch sockets
- ½-inch air gun
- Set of 3/8-inch sockets
- 3/8-inch ratchet
- Common screwdriver
- Floor jack
- 4 jack stands
- Set of wrenches
- Tie rod and ball joint separator tool
- Hammer
- Engine support stand crossbar with chains
Warnings
- The frame itself is too heavy for one person, so one or preferably two helpers will be needed when it is ready to be removed. It is advisable not to stand under the vehicle when this is removed.
Writer Bio
Don Bowman has been writing for various websites and several online magazines since 2008. He has owned an auto service facility since 1982 and has over 45 years of technical experience as a master ASE tech. Bowman has a business degree from Pennsylvania State University and was an officer in the U.S. Army (aircraft maintenance officer, pilot, six Air Medal awards, two tours Vietnam).