Moving driver seat back?

[PGG]

I am a pretty big, fat, old man and would love it if there was a way to move the drivers seat back even a inch or two. Are there any good options for this?
I was hoping something that didn't require drilling more holes or something.
I had to put some brackets on my FH40 seats to drive it too.
The seat along with the GIANT steering wheel that is not adjustable makes for a kind of tight fit.

I guess I need to loose 20 anyway but more leg room would be nice.

Thanks PG

[bamachem]

In my 72, there is an extra set of threaded holes about 1.5"-2" farther back - but only for the rear mounting bolts for the driver side bucket seat. There's no way to mount the front feet for the seat if you use the rear holes that are farther back. I have some galvanized flat bar, 1/4" thick and 4" wide that I am using to make some relocation brackets for the front mounting points.

What will that entail? Cut two sections of the flat bar stock so that I basically have 4"X4"x1/4" thick squares of steel. Use the front feet to mark the bolt pattern in the plates. Drill those two holes, rotate flat bar stock 180-degrees and use the holes and factory seat bolts to bolt the plates down to the floor hump where the seat normally attaches. Then, set the seat on top of them and line up the rear most holes in the floor again. The front seat "feet" should land on top of the galvanized plates I just inatalled. Now mark the holes for the front legs/feet where they fall on the new plate.

Remove everything and drill two more holes where you just marked the plate, insert some GRADE 8 bolts and weld them to the plate so they are essentially studs protruding up to line up with the seat brackets. I'll add some ~3/4" thick high density rubber underneath the relocation plates to help support the weight of the seat and spread the load across the floor. Also, I'll have to make sure to paint the galvanized plate black to blend in with my bedliner floor...

Install seat rear mounting feet into the rearmost holes, and install the front feet onto the new relocation plates. I'm planning on doing this one evening this week.

I'm 6'5" 245lbs so a couple more inches of leg room will be nice.

[PGG]

bamachem thanks for the post. I am sure you really need it as I am a lot shorter then you. If you have extra material make two sets and sell me one set!

Thanks PG

[truckster]

Originally Posted by bamachem

....weld them to the plate so they are essentially studs protruding up to line up with the seat brackets.

You're not planning to weld that galvanized steel without removing the zinc, are you? That's a bad idea. Not only will it give you a bad weld, but it could kill you if you inhale enough of the zinc fumes.

[cleszkie]

How about swapping in a tilt column? That would buy you some more room without the hassle of moving you seat back. Put a smaller diameter steering wheel on there and you won't know what to do with all the space.

[bamachem]

Originally Posted by truckster

You're not planning to weld that galvanized steel without removing the zinc, are you? That's a bad idea. Not only will it give you a bad weld, but it could kill you if you inhale enough of the zinc fumes.

Yes, I plan to grind the zinc back to reveal bare carbon steel where I want to weld the bolt head to the plate. I understand zinc oxide lung contamination for galvanized welding as well as the side effects. Although not deadly, it can make you feel sick. The remedy is bedrest and hydration while treating the headache with OTC meds. I'm not going to take chances with my lungs at any rate and grind back all zinc in the general area. It can happen with other alloys such as nickel as well, so it's not just zinc that you have to worry about, either.

[bamachem]

Originally Posted by PGG

bamachem thanks for the post. I am sure you really need it as I am a lot shorter then you. If you have extra material make two sets and sell me one set!

Thanks PG

Let me see what it involves but I might have enough scrap flat bar to make another set.

[PGG]

Originally Posted by bamachem

Let me see what it involves but I might have enough scrap flat bar to make another set.

Sweet I am happy to make it worth your trouble I am the non helpful type!
Can send paypal, money order or a check whatever.
Thanks PG

[bamachem]

This is the bolt pattern in the floor of my 72 K5 where the REAR feet of the driver seat mount. The holes on the left line up with the seat. The holes on the right were plugged with extra bolts. All holes appear to be factory, with captive nuts below. I plan to move the seat back to utilize the mounting holes on the right.



Here's the plate I used. 4" wide X 1/4" thick galvanized flat bar (carbon steel). I cut two 5" long sections.



First step is to unbolt the front feet of the seat and to just loosen the rear bolts - but do NOT remove them from the original holes. Slide the steel plate under the feet and line it up with the edges of the OEM seat frame and mark the holes. Mark the plates for both feet.



Drill the holes and mount the plates to the floor using the OEM bolts.



Now take the rear seat mounting bolts out of the original holes. Slide the seat back and then put the bolts in the rearmost set of holes. Now you can see that the front feet slide back and onto the plates you just mounted up front. Mark where the new mounting holes need to be, remove the plates, drill the holes. Go ahead and paint the plates at this point before you install them back in the truck. Paint all edges and holes well. Finally mount the plates with the OEM bolts on the floor hump again.

NOW USE HIGH-GRADE HARDWARE TO MOUNT THE SEATS TO THE PLATES - Grade 5 or Grade 8.

No need for welding anything as you can easily get to the bolt heads and the nuts. I would suggest using a split washer on each to make sure they don't loosen up with time/vibration.

Result? About 2" of additional leg room! It's almost too much leg room now.

[my71gmc]

http://67-72chevytrucks.com/vboard/s...d.php?t=526167

[PGG]

Well I am not a lucky guy there are no such extra holes in my floorboard.
Now what do I do?
Anyone else found they only have one set of holes?

Thanks PG

[PGG]

If I get rectangular steel tubing 5x2" to make four new footings what thickness should I get? I am thinking four pieces cut into 5" sections cut the front half off
drill bolt holes to bolt into the floor. Then drill holes in the back of the sections for bolts it would move it back 2" and up 2". Anyone think that is too much?
I think I would like the seat taller also but I could be wrong after all that work it would suck if it was not comfortable. The thicknesses are shown below. I think either of the first two would be heavy enough but what do you experts say?
Do you think this is a good option?
Thanks PG

5” 2” 11 0.120
5” 2” 3/16” 0.188
5” 2” 1/4” 0.250

[A1971Blazer]

Before you decide....take the seat loose and just set it up on some 2x4 blocks or similar, to get it where YOU think it's best....then figure out what metal you'll need. The 2x5 rectangle tube would be plenty rigid in 11 gauge thickness.
It may look a little "jerry rigged" though?
Just my 2¢.....easier than losing 25 lbs.

[smbrouss70]

Originally Posted by bamachem

This is the bolt pattern in the floor of my 72 K5 where the REAR feet of the driver seat mount. The holes on the left line up with the seat. The holes on the right were plugged with extra bolts. All holes appear to be factory, with captive nuts below. I plan to move the seat back to utilize the mounting holes on the right.



Here's the plate I used. 4" wide X 1/4" thick galvanized flat bar (carbon steel). I cut two 5" long sections.



First step is to unbolt the front feet of the seat and to just loosen the rear bolts - but do NOT remove them from the original holes. Slide the steel plate under the feet and line it up with the edges of the OEM seat frame and mark the holes. Mark the plates for both feet.



Drill the holes and mount the plates to the floor using the OEM bolts.



Now take the rear seat mounting bolts out of the original holes. Slide the seat back and then put the bolts in the rearmost set of holes. Now you can see that the front feet slide back and onto the plates you just mounted up front. Mark where the new mounting holes need to be, remove the plates, drill the holes. Go ahead and paint the plates at this point before you install them back in the truck. Paint all edges and holes well. Finally mount the plates with the OEM bolts on the floor hump again.

NOW USE HIGH-GRADE HARDWARE TO MOUNT THE SEATS TO THE PLATES - Grade 5 or Grade 8.

No need for welding anything as you can easily get to the bolt heads and the nuts. I would suggest using a split washer on each to make sure they don't loosen up with time/vibration.

Result? About 2" of additional leg room! It's almost too much leg room now.

I just made this modification since my Blazer originally came with Utility Buckets and I was changing over to Sport Buckets and this would keep me from having to drill more holes in the floor, plus I am 6'1". I just wanted to thank you for the idea, it made a huge difference in the comfort of driving my Blazer around. The only thing I did different was weld some nuts to the bottom side of the plate so that I could just run the bolts down through the seat bracket and screw them in. Thanks.