Chevy Wide Ride IFS Installation Instructions

1. Prep the truck by removing the front sheet metal, engine/trans, battery and fuel tank & lines
2. Raise the truck up on jack stands. Put the front stands under the frame and just ahead of the front cab mounts and the rear stands back by the rear spring mounts. Make sure that the truck is level side-to-side and front-to-back. Shim as needed – then double check this. – VERY IMPORTANT –
3. Use a level or plumb-bob to make the original axle centerline onto the frame, rails, and the ground on each side. Straight axle trucks use the kingpin center, I.F.S. trucks use the lower ball joint. DOULBE CHECK YOUR MARKS.
4. Remove all of the stock suspension parts. Including the main crossmember on I.F.S. trucks.
5. Use a straight edge or chalk line to connect the two C.L. marks that you made on the floor. Use a level or plumb-bob to transfer this C.L. up to the frame rails. Compare this with the C.L. marks that you put on the frame. Double check each side to a common point – like a cab mount hole – on each side, and adjust these marks to the best you can, for an accurate C.L.
6. Now that the new axle centerline is marked, the fun begins. Center punch the mark in each frame rail. Clean the rails from the cab mounts to the core support – inside and out. Re-draw the centerline using a straight edge across both frame rails. Draw one line 2” in front, and one 2” behind the centerline
7. Measure the inside width from frame rail to frame rail to frame rail. Measure the width of the crossmember (fig. 4). The crossmember is a little wider than the rails will allow. Calculate how much to grind out. The magic numbers should be close to 1/8” of an inch in most cases. This is how much needs to be ground out of the frame rails.
8. Notch the rails – top and bottom to fit the crossmember.
9. Set the crossmember into the rails. Rack mounts in front. Check the alignment with the centerline. Check it side to side to make sure it is centered. Check to see that the upper ledge of the crossmember sits flat on the frame.
10. At this time you should take a minute or two to double check everything. This is it, make it a good one.

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