Question: Swapping C4 seats for C6 seats

[jamison]

I just picked up a set of C6 seats cheap off of craigslist for my C4. I was wondering if anyone has done anything like this? It looks like i'm going to have to use the mounting brackets that came with the seats that attach to the slide rails but i'm not sure. both the C4 and C6 seats have very similar dimensions. so its mainly mounting them in my C4 that i'm not sure about. any help or suggestions would really help. and if i'm the first to ever post or do this on this forum ill be sure to post up what i did once i figure out how to get them mounted in my car.

thanks, jamison

 

[Schrade]

If they're not plug and play, I'd use the mounting frames existing in the C4, instead of drilling in the floor for the C6 mount frames.

You drill in the floor, and you might strike oil - (or worse!!!) - and not be able to get it capped YIKES yuP!!!

 

[jamison]

ok after pulling out my passenger seat i see that there is no way i can use the stock mounting brackets on the new seats. im going to either have to try to make some metal brackets that bolt to the original seat mounting bolts that will then extend new bolts to where the new seat brackets need to be. or im going to have to just have to drill new mounting holes and brace it under the car.

if any one has a wiring diagram of the C4 power seats that would be helpful i have looked around and cant find anything on them.

thanks, Jamison

 

[Rex S]

This is a project that just isn't worth the effort. Take a close look at the C4 seats VS the C5s. C4s have a much higher quality seat. No offense to C5 owners but GM really cut corners with the seats.

 

[Schrade]

It might well NOT be worth the effort...

But if you're determined, you should probably FIND a way to get the new leather onto the existing mount frames.

How exactly is the mis-match? ON-plane, or OFF-plane? I'm guessing the 4 bolt holes don't match, BUT, are they on the same PLANE? To put it differently, if you take the C4 seat off of the mount frame, would it sit flat on the floor - all 4 bolt points? And the same question for the C6 seats - do all 4 bolt points sit on the floor flatly?

If so, it won't be too much a problem nope. But if the mismatch of off-plane, forget it. You'd be fabbing in 3D, and that's gonna' take a computer.

 

[jamison]

both the C4 and C6 seats have the brackets riveted on to the rails and there is no possible way to use the old rails on the new seats. they are too different. today i looked into it more and all that mounted the old seats is 4 bolts and 2 very thin pieces of metal under the car on the floor pans. so im just going to make new mounting spots for the C6 seats and put new metal plates under the car. the C6 brackets span measure 21'' front to rear where as the C4 brackets measure 16'' front to rear. the floor pan is pretty flat so i should have any issues.

 

[WhalePirot]

=C4s have a much higher quality seat.

I had a C6, briefly and quickly found the C-4 seats more comfortable.

Fitment may be a minor issue compared to the electronics involved, when you consider memory seats, especially IF set-up for Driver keys 1 and 2. I bought a gorgeous set of BMW black leather seats on CL and it is a MAJOR project just to get the many motors to run!! .... think CANbus. One possibility is to disassemble the seats, remove all the circuit boards and employ 6-10 relays, IF the switches can handle the current demands for the relays.

 

[jamison]

I completely forgot about this thread... Im so sorry I never finished it. Well it is over two years old now and I've had the C6 seats in my car just as long. I had to just get rid of the old mounting spots since they were in the way of the new rails. I wanted to keep them so I could go back to stock but there was just no way if I wanted to get the seats as low as possible. To mount them I just had to drill holes in the location were the C6 mounting holes were. Then I used grade 8 bolts, washers, and nuts. As for wiring I had no problem as well. All you need to find is a wire diagram to find the positive and negative wires on the C6 seats. In my 90 there were two connectors, one for seat positioning and the other was simply power. My father has a C6 and he has the dual driver seat memory but there must be a separate relay or something for that. Because my seat just stays right in place and the same for the fully powered passenger seat. So in short if you find the C6 seats more comfortable then your C4's and you're lucky enough to find a practically brand new set on CL for $400 like did... They will fit with a little elbow grease!

 

[WhalePirot]

date check

Dang.. gotta start checking them.

Still, useful info for others.

Apologies to the guys who are more current on the threads.l

 

[catso]

I completely forgot about this thread... Im so sorry I never finished it. Well it is over two years old now and I've had the C6 seats in my car just as long. I had to just get rid of the old mounting spots since they were in the way of the new rails. I wanted to keep them so I could go back to stock but there was just no way if I wanted to get the seats as low as possible. To mount them I just had to drill holes in the location were the C6 mounting holes were. Then I used grade 8 bolts, washers, and nuts. As for wiring I had no problem as well. All you need to find is a wire diagram to find the positive and negative wires on the C6 seats. In my 90 there were two connectors, one for seat positioning and the other was simply power. My father has a C6 and he has the dual driver seat memory but there must be a separate relay or something for that. Because my seat just stays right in place and the same for the fully powered passenger seat. So in short if you find the C6 seats more comfortable then your C4's and you're lucky enough to find a practically brand new set on CL for $400 like did... They will fit with a little elbow grease!

I know this is an old thread, but very helpful nonetheless. I'm thinking of doing the same, but probably just using the cushions; not the entire seat mechanisms. I will report back after it's done.