'92-99 Seat Install in Squarebody Suburban

[cal30_sniper]

As promised, here's the writeup on how I put leather seats out of a '96 Suburban into my '86 3/4 ton. Surprisingly, it wasn't that difficult. It took me two days including mock-up and measurement, modification, painting time, and clean-up. Knowing where to make the cuts and how to set up the front rails, as well as having a buddy to help bolt through the rear seats would have cut the time down to less than a full day.

Here's the steps:

1. Remove front seats and remove both seat tracks (save all bolts)
The '92-99 has a flat front floor pan, so you will need to swap your factory bucket seat tracks over to the newer seat in order for them to sit correctly. Unfortunately, you will lose the power seat motors when doing this.

(comparison of '96 and '86 front seat tracks)


2. Cut and redrill factory seat tracks to match the newer seats. The newer seats use a 14" wide x 13.25" long bolt spacing, where the old seats are around 13.25" wide x 14" long. In order to bolt the old rails onto the new seats, you will need to modify the old seat rails. I used a sawzall to cut off the "c-channel rails" of the last 1" of the front of the seat track so I could redrill a bolt hole at the very forward outside corner of the track. At the rear of the track, I used a large washer which overlaps the very back corner of the seat rail. The pad on the rear of the rail was not big enough to fully reach the rear corner bolt hole on the new seats. I will be taking them to a friend to get a larger pad welded on here so I can bolt it together correctly. Also, the newer seats have two sets of bolt holes. The factory rails are bolted to the new seats using the outside set of holes on the outboard side of the seat, and the inside set of holes on the inboard side of the seat. In order to get the seats to center up on the old rails, you will need to thread the outside set of holes on the inner side of the new seat and bolt the old seat rails to that location. I used the bolts I removed from the seats to thread their own holes, and it worked like a charm. See photos below for finished mounting of the front tracks (minus the welded pad portion at the rear which hasn't been done yet.



3. Mount the front seats. Using the technique described above, the seats will be centered, at the right angle, and will have a full range of motion. I kept the '86 seat belts up front for simplicity's sake.

4. Remove all second row seat equipment. You will now need to take out the seats themselves, as well as all latches, seat belts, bump stops, and the long hinge that attaches to the floor.

5. Cut 2nd row seat tracks to clear the floorboard. The center rear sections of the 60/40 seat mount must both be notched to clear the floor pan. The 92-99 suburbans had a flat floorboard all the way back to the 3rd row seat. Because the 73-91 has a sharp rise in the floor just aft of the 2nd row, it is necessary to notch the second row seat rails in the middle in order to clear the angled portion of the rise that exists in the center of the floor pan. I used a sawzall and a cut-off wheel to do this, and then filed and painted the finished edges to prevent rust. The photos below show the before and after pictures of where the cuts were made. Note that only the center sections of the rails had to be notched. The outer corners will back right up to the rise since the floor pan is flat there on the 73-91. I made it a point to avoid the follow creases in the track when I made these cuts. Not only did this maintain a factory appearance, it also helps maintain the rigidity of the tracks.

(60% side before)



(60% side after)



(40% side after)



6. Cut Blocks for height. In order for the 2nd row seats to fit correctly over the transmission tunnel hump, 3 wood blocks need to be cut in order to properly space the height. I used 2"x1" Red Oak from Home Depot, as it seemed to be the densest and most durable wood available. You will need one 6" long block, and three 3" long blocks. The photo below shows the location that the blocks will be placed under the seat rails.



7. Place the second row seats in their location, and put the blocks under the bolt holes indicated. Take measurements on both sides, as well as from the rear of the seat to the 90 degree bent where the old seat hinge mounted. Make sure everything is lined up and the 60/40 seats are nut rubbing on each other in the middle. (the carpet and underpadding should still be in place for this).

8. Once the seats are properly located, use a 1/2" drill bit to drill through the wood blocks and/or floorpan under each bolt hole on the 60% side. There should be a total of 8 holes for the 60% seat.

9. Use a 3/8" drill bit to drill out the blocks and floorpan under the front two holes of the 40% side.

10. Remove the seats. Remove the trim holding down the carpet, and peel the carpet and underpadding back to the front seats. I took the time to clean and paint this area, as well as the holes that I had just drilled. This left a nice clean look in the gap behind the 2nd row seats when they were finally installed. The photos below show the floor pan before reassembly.




11. Place the blocks directly on the floorpan in the proper orientation. I painted the blocks before doing this in order to help prevent them from soaking up moisture and becoming soft or cracking. I also installed them when the paint was slightly tacky so they would dry and stick to the floor pan with less tendency to move around while I installed the seats. The purpose of putting the blocks under the padding and carpet is so that you can't tell that they are there when the carpet is put back down and the seats are bolted in.

12. Lay the carpet back down, and drop 3/8"x3" bolts with washers through the holes in the space blocks. This ensures that the carpet holes are properly lined up with the block and floorpan holes, and that they do not shift during installation of the seats.

13. Install the seats, remove the 3/8x3" placeholder bolts, and bolt down the seats with the proper hardware. I used grade 8 1/2-20" bolts for the 60% side seat (holes drilled with the 1/2" bit) and grade 8 3/8-24" bolts for the 40% side seat (holes drilled with teh 3/8" bit). Note that if you have a factory dual exhaust system, the heat shields may have to be loosened under the vehicle to reach the bolts. I passed the bolts through from the top with 1/2 washers between the head and seat rail. I then used another 1/2" washer, lock washer, and nut underneath the car. Here's where it comes in real handy to have a friend to help tighten down the bolts.

14. With the front two bolts installed on the 40% side seat, flip the seat bottom up and pull the mechanism on the seat track which allows the seat to slide forward. This will allow you to reach the back two bolt holes under the seat tracks. The newer suburbans allow the 40% seat to slide forward in order for easy 3rd row passenger exit. The rear two holes are now drilled out with a 1/2" drill bit, and bolted through the floor pan. Once the bolts are tight, slide the seat to the rear and ensure that it is latched.

15. Install the factory plastic seat track covers if desired for a cleaner look.

16. Drive and enjoy your new-found comfort!

Here's the finished pics:







As soon as I get home I'll try and remember to post exactly what length of 1/2" and 3/8" bolts I used. I'll also post up once I figure out how to mount the third row seat, and second and third row seat belts. Thought y'all might enjoy seeing how simple this modification was though. These seats are all over craigslist right now, I picked up all 3 rows for $200, and the hardware to mount them was only an extra $30 or so.

-cal30sniper

[Cherub]

looks good

[68Timber]

You did a good job on that. Once the front tracks are corrected to bolt-through to the seat, it'll be about perfect.

[Mr. 250r]

I put 2000 or 2002 rear seats in mine as a mock up and they sat like up against stock suburban bucket seats and they were against the raised floor pan in the rear maybe i did something wrong cause i really want them in the back lol good write up

[kwin]

I'm amazed by how much different the suburban bracketry is compared to the Tahoe brackets.
Fantastic write up !
You need to be writing service manuals, technical writer there is a career option for ya!

Thanks
Keith
Posted via Mobile Device

[cal30_sniper]

Originally Posted by kwin

I'm amazed by how much different the suburban bracketry is compared to the Tahoe brackets.
Fantastic write up !
You need to be writing service manuals, technical writer there is a career option for ya!

Thanks
Keith
Posted via Mobile Device

Thanks man. I've been getting a lot of technical writing practice on my Aerospace Master's thesis as of late, haha.

I've never seen the Tahoe brackets, but I've hears they're quite different. From what I was reading, they might be an even better fit than the suburban seats. I just couldn't pass these up for $200 though.

-cal30sniper
Posted via Mobile Device

[lt1fire]

Old thread but does anyone have the pics that went with it?

[N2TRUX]

Originally Posted by lt1fire

Old thread but does anyone have the pics that went with it?

You might try to message the OP. Hasnt been on since
Last Activity: 06-13-2015

[cal30_sniper]

Just saw my photos were down when trying to reference this for another guy. I’ll have to try and boot up the old laptop to reload them. Good job, photobucket.

[87_Burban_454]

I know it has been a while but any luck with the pictures? I recently got the seats I want to swap in and the visuals will definitely help.

[BlueJeep]

I'm interested in this too! I'm wondering about 2000-2006 seats.