Power seat buzzing

**Dr. Overkill** · 09-01-2009, 10:55 AM

Gang,
The front-back adjustment on my driver side power seat ('97 2-door hoe) is jacked. It buzzes and doesn't move (well, sometimes it moves a little). It sounds like a gear is either stripped or only making partial contact with whatever other gear it's supposed to mesh with. I've never had one of these apart to know how they work.

BTW, the vertical/tilt mechanisms still work just fine.

Anyone have this happen and can direct me as to what I'll need to repair it? I'd prefer to remove the seat just once to fix it, rather than R&R to diagnose then R&R again to fix once I get parts.

Eyeballing under the seat, it looks like there may just be one module that does everything and I may have to replace the whole thing rather than just the front-back part, but that's just a wild guess.

thanks!

**NoEcm** · 09-02-2009, 09:08 AM

I've got the same problem except it's opposite of yours. Mine buzzes going up and down. Front to back it works fine.

Anyone have any solutions or thoughts?

**NoEcm** · 09-02-2009, 07:15 PM

I took mine apart this afternoon.

To fix it, you'll have to replace the gear mechanism (the aluminum cased thing that the motors are attached to).

I drilled mine apart to see what was wrong. All the gears were intact and in good condition but one plastic bearing and the inside housing that holds the gears together was broken.

I was able to rig the thing back together so it works but it looks like I'll be searching the wrecking yards to find a replacement.

**Dr. Overkill** · 09-02-2009, 09:17 PM

Thanks for the update. So by drilling it apart and having to rig it back together, you're saying it's not really a user serviceable part?

If you find more than one of those, let me know. If I can't find one locally, I may hit ya up for a favor :)

**NoEcm** · 09-02-2009, 10:41 PM

Nope, it's not a user servicable part............unless you have access to a lathe and vertical mill to re-create the broken plastic part(s) and ~ 4 - 5 hours of free time to machine the parts.

At this point I have 2 options.
1. Search the local wrecking yards for a replacement gear mechanism and hope it doesn't have the same broken parts.

2. There is a guy on Craigslist selling seats from a 1999 Suburban. The drivers seat is torn and he wants $25 for it. I can strip the gear mechanism from this seat. He is 50 miles away from me so this is option #2.

Good luck

**NoEcm** · 09-03-2009, 07:58 PM

Fixed!!!!

$6.50 + tax for a gear mechanism and motor(s) at the local Pull A Part.

**Dr. Overkill** · 09-03-2009, 11:57 PM

Wow, that's a deal! Did you replace more than just the silver thing? I still haven't pulled my seat out yet to look at what all is under there. Got pix? :)

**NoEcm** · 09-04-2009, 09:34 AM

Sorry, no photos.

Pull A Part wanted $16.50 for a complete SUV seat or $6.50 for the seat motor.

The leather portion of the wrecking yard seat was trashed so I took the seat off and disassembled it in the yard.

To get the gear housing and motor off you have to proceed as follows:

1. Remove seat from vehicle (15mm socket and box wrench)

2. Once the seat is removed separate the seat base from the seat (10mm socket and box wrench)

3. Split the left and right sections of the seat base. Depending on the year, you'll use either a 15mm socket or a pair of pliers to remove the 2 cotter pins.

4. Remove gear housing and motor from seat base as one unit. (3 bolts, 10mm socket)

5. Reassembly. Make sure you index the left side seat base to the right side correctly. The easiest way to check this is to bolt the base into the vehicle and make sure all 4 mounting holes line up to the floor. If all 4 mounting holes line up, remove seat base, bolt it back onto the seat and install the assembly back into the vehicle.

On a side note, I used my old electric motors with the new gear housing. My motors were in a known condition and working strong.

Good luck!!!

**Dr. Overkill** · 10-11-2009, 06:54 PM

Mine is now fixed too, but I didn't get off nearly as cheap as you. The pull-a-part type yards in my area are a pretty good drive away and don't keep an inventory listing so they couldn't tell me if they had a compatible vehicle. I didn't feel like spending hours wandering through their lots, especially since it was over 100F here at the time... So I went to a closer truck/van specialty yard and got a complete seat base assembly for $50+tax. Yeah, I wasn't too thrilled but I'm assuming I still made out much better than buying new from the General.

I wish I would have re-read this thread before diving in, though. I couldn't see how to separate the gear housing and motor, so I just swapped out the entire assembly. I'm not so jazzed with that because it has plenty of surface rust (the 'burban or hoe it came out of was missing the drivers door) and the tracks had a ton of play compared to mine. I thought the seat was going to rock all over the place once installed, but it's actually solid. Everything works well although there's a small hitch in one of the tilt gears. But considering how rarely I adjust the seat, shouldn't be a problem.

When I have the time and energy I might pull it back out and see if I can't swap the gear and motor assy back over to my tracks. I couldn't see how to split the left and right sections, though.

One thing I did learn is to raise the seat up to the max height, and (if possible) center it forward/backward before doing this. My seat was completely down and it made it a complete bear getting the bolts out of the floor, and 2 of the bolts holding the rails to the seat were a butt to get to as well.

For those who are interested, here are some pix of the assy I pulled out of my hoe.

Bottom

Top

Close-up

**NoEcm** · 10-11-2009, 09:25 PM

Congrats on getting your seat fixed. $50 isn't really too bad when a new part would have probably cost you ~$200.

To get the gear housing/motor off, you have to seperate the 2 halves of the seat base and then you can pull the housing/motor off as one unit.

One thing to remember (especially for reassembly). The middle rod has a drive shaft going through it to drive the left and right seat track gears. These gears need to be "keyed" to each other. This is what keeps the left and right seat tracks synchronized to each other.

**Dr. Overkill** · 10-12-2009, 08:10 AM

Originally Posted by NoEcm

To get the gear housing/motor off, you have to seperate the 2 halves of the seat base and then you can pull the housing/motor off as one unit.

One thing to remember (especially for reassembly). The middle rod has a drive shaft going through it to drive the left and right seat track gears. These gears need to be "keyed" to each other. This is what keeps the left and right seat tracks synchronized to each other.

I just saw what you said in your earlier post about the 15 mm bolts--I'm too lazy to go out to the garage right now, but in looking at my pic, that looks like what I have (I don't see any cotter pins).

So to synch the two halves, would it be better to run the seat all the way back before removing it? At the very least, it would match the assembly I removed, because it was all the way back too.

**NoEcm** · 10-12-2009, 12:54 PM

Originally Posted by Dr. Overkill

So to synch the two halves, would it be better to run the seat all the way back before removing it? At the very least, it would match the assembly I removed, because it was all the way back too.

That would work.

Also, when you are done putting the lower half together, bolt it to the floor pan with bolts only on either the left or right side and run the track forward and backwards to make sure everything is in sync.