OK guys, despite the numerous people saying it was impossible...it's now complete. I've retrofitted the center (7th seat) into a 2006 R500. It's actually not all that complex, figuring out the right parts to order was the hardest part.

Here are the steps:
1. remove arm rests (search forum) pretty easy...remove the carpet on the back, undo the leather, and almost directly under the cusion, there's a pin to pull, and the arm rest comes off as once piece (this is my short example). There were pictures on how to do this on this forum.
2. now remove the 2 captain chairs, you'll need to replace the belt buckles, with smaller thinner ones, see my picture. The cover, is held on by a torque screw at the bottom, and just be gentle when taking it apart after that, it's clipped in.
3. after removal of both seats, remove the side trims/sills...just pull, no screws just clips.
4. now pull carpet up, and tie something to hold it open, and you'll now see the predrilled holes and screws sticking up for the brackets...install, then cut carpet, then bolt down seats and put it all back together.

All in all, about a 3 hour job, and not all that complicated, once again, getting the right parts was painful. Total cost, about $600. But I was able to find the center seat, and seatbelt for about $200 from ebay...now for the good parts

 

and the last ones...

 

1. seat: from ebay, came with seat belt, so i can't help with those parts
2. seat buckles: need to replace the 2 in the car now (the existing 2 in the car are too big, and smaller ones are used to fit the 7th seat, and 3rd for center seat. was about $80 total...2 of these A2518602769 and 1 of these A2518602469
3. there are 2 seperate cross members, front is A2516100426(25 euro) rear is A2516100326 (40euro)
4. all misc bolts about $30...N 910112 008000 Need 4; A202 990 13 01 need 2; N000000003175 need 2

I'm happy it's done...but to be honest, I don't like it. The car is less roomy, the center seat doesn't slide to match the positions of the other 2, so they're constantly all the way back to match, which crowds the back seats, and the center also doesn't recline back as far as the other 2 captains chairs. So as soon as I don't need the center seat, I think I'll remove it since it really wasn't all that complicated.

 

Add to the parts list:
N913023012002 - need 4 to mount the seat to the cross-members. The Mercedes description is Nut, Seat Mounting M12X1.5. Note that Mercedes dealers in northern California at this time have the right description but are handing out M10 (10mm) nuts. These will not fit. Either have them re-order them or get the right size from a store that specializes in nuts/bolts as an alternative.

I completed the same installation on an 07 R320cdi using these instructions. Works great and increases storage capacity by a lot. Besides, the arm rests were just taking up space.

Unplugging the harness under each captain's seat prior to removal of the seat may trigger a fault code for the SRS system. If so, it will show on your dash display on startup. Mine did, David Bho's did not. My friendly mechanic cleared the code from the system memory in a minute.

BTW, the arm rests are easy to take out - peel the back cover off the seat just around the arm rest. You don't need to peel the entire cover. Behind the cover and next to the arm rest you will see the foam seat cushion. Push aside the foam til you see the steel shaft for the arm rest and a plastic sleeve. Keep looking and you will see the ends of a metal retaining clip about 3" long with two prongs. This needs to be pulled/pushed off the arm rest as its what holds the arm in place. If you see the top of the clip, just pull it toward you with some pliers. If you see the prongs, push them back. In my case, I pushed one clip and pulled the other. Depends on orientation of the clip. Once that's done, just rotate the arm to about half-way between vertical and horizontal and gently pull the arm rest out. You are looking for the spot where the arm will pull free. Its there, but it might take some minutes of rotating the arm to find the spot. When you find it, the arm will slide out easily. Then put the seat cover back in place and press it into position along the edge.

 

this is what I referenced when i removed the armrest...

http://www.benzworld.org/forums/w251...-arm-rest.html

 

Hi,
I am looking to put a centre seat into a 2007 R350.
Does anyone know where I can get a seat someone doesnt want?
The seats in my car are the black vinly or pleather( plastic looking leather).

I tried ebay but there doesnt seem to be any listed.

I am from Australia but I dont mind paying shipping if I can get a reasonabily priced used one. I presume a new one would be astronomically expensive.

Also where in Germany did you order the mounting plates and bolts and extra thin plug seat belts?

Thanks for any info.
Regards Hanns

 

Check with Carlos Duarte : Carlos Duarte <caduarte@LKQCORP.com>
He works for the largest parts recycler in the States and got me my seat. LKQ has yards all over the country. Also check car parts.com for listings of wrecking yards and recyclers. The seat belts came from LKQ with my seat, but should be readily available from dealers. The plates and bolts came from Mercedes here in the U.S. once a dealer requested that their part numbers be added to the U.S. inventory list. Dealer may have to order them from Germany, but the part numbers are in the U.S. system.

 

Thanks for the info.

Just want to check that the middle seat can be put in a 2007 R350.

Are the mounting points in the car for the plates and fittings, before I check with Carlos? Thanks
Hanns

 

Mine is a 2007 R320cdi which at least here is the same car, but with a diesel engine. David's is a 2006 R500 - same car, different engine. At least in the U.S. and Canada, there was only one body style used for the R class. In both cases, all the holes and fittings were in the frame and floor pan. We both pulled out the existing seats, cut away the carpet and then you can bolt in the mounting brackets and the seat belt brackets. Drop on the seat and bolt it down. David's directions are spot on. It may even be possible to do this without pulling the other seats, but I wouldn't do it that way.

 

Thanks for the info, the body style and shape is the same. The wife has the 2009 model R 280CDi and it has the same interior and body but the 7 seat version, so wish me luck. Ill try to get everthing off Carlos. Thanks Hanns

 

Finally got around to installing the seventh seat in my originally six-seat R320 CDI LWB this afternoon.

Got the seat from a wrecker in Sydney with all mounting hardware, but quickly learned that the two black mounting brackets are different for short and long-wheel base cars, and my new seat had come from a short wheel base. Ordered the new brackets, and, as DavidBho says, its a three-hour job.

However, I didn't remove the seats entirely - you can unbolt them and tip them sideways to get the carpet up - saves mucking around with the electrical connections.

I'm pretty happy with it. It was a bit daunting cutting into the carpet, but it looks fine, and it makes the car far more flexible for a family of five plus greyhound. And my wife is very pleased, so life is good.

One more thing - If you are replacing a centre console with a seventh seat, keep the carpet that you need to cut out to accommodate the new seat. You can use the offcuts to fill the space left quite successfully, using contact glue and bit of cutting and shutting. Black carpet, like mine, may be more forgiving than lighter colours. You'd never know it was patched.

 

I'm wondering if there's anywhere I can get the parts especially the mounting hardware? I tried to search those part number on mercedes parts website but only got some of them. I can find the front cross member but not the rear one(A2516100326).

Just got a seat from a junkyard but no hardware...

 

Good morning David, I'm new to the forum and just read your post relating to the seat retrofit. I have a 2006 R350 and I am in the process installing the 7th seat for my wife but have a slight delay. I will like your advice on locating those cross members Pt# A2516100426, A2516100326. Where did you purchase them.

thanks in advance for your help

 

Good morning genius, I'm new to the forum and just read your post relating to the seat retrofit. I have a 2006 R350 and I am in the process installing the 7th seat for my wife but have a slight delay. I will like your advice on locating those cross members Pt# A2516100326. Where did you purchase them.

thanks in advance for your help

 

Pretty interesting story. I called the stealership the other day to locate this part and they told me that it looks like they changed the part number to A2516100526 for no reason. So I asked them to order both cross members for me and they told me it's going to cost a few weeks time since this one has to be shipped from Germany. I ordered them and finally after a month I got them today. I'm not sure if it's the right parts since I haven't tried to put them on probably will do this weekend and I'll post to let you know if they are the right parts. Right now I'm in doubt of that.

 

Finally got time to install the seat this weekend. The parts I ordered fit perfect and you can go ahead with them. The A2516100326 has been replaced by A2516100526 and the other part you need is A2516100426. I got both brackets from www.getmercedesparts.com that's basically MB of Annapolis and the total was $109.xx. I asked my local dealer and they quoted me for $2xx.xx for those two.

You'll need 4 M8x1.25 nuts to mount the rear bracket to the chasis and 2 M8x1.25 bolts for the front bracket. Also you need 2 bolts to mount the seatbelt and buckle of the middle seat to the rear bracket(I don't have the size but they are the same as the ones for the seat buckles of the other seats, probably M10x1.5). The 4 nuts that hold the seat to the brackets are M12x1.5. I used 4 lug nuts I bought from advanceautoparts to do it and it works perfect. The most tricky part is to cut the carpet. I only cut the holes for the 4 mounting studs and for the front bracket I need to cut some foam off the carpet to make room for the front bracket.

 

I need the whole assembly, so if anyone wants to get rid of it, just send me a reply or PM.

Many thanks!

 

All these parts are available for purchase in the US Market. <br/>Most people would need these Track Covers.<br/>#16- 25192010868K67 Seat Track Cover Center Front, Buckskin color(Tan)<br/>#17- 25192012868K67 Seat Track Cover Center Rear, Buckskin color(Tan)



#40- A2516100426 Front mounting bracket.<br/>#50- A2516100526 Rear mounting bracket.<br/>#45- A1409900317 Bolt, M8x24, Qty 2<br/>#60-1- N910112008000 Nut, M8, Qty 4<br/>#60-2- N913023010002 Nut, M10, Qty 2<br/>*Qty as listed on the database for reference only.

 

#2- 25186024699051 Buckle with 3rd seat(7th seat) Qty 2.



I never had to try this as of yet, but I'm almost certain that the outer cover can be removed to use the inner casing by itself for the w/3rd seat application.

 

#110- 2518602469 ? Center seat buckle, Mounts to the rear seat mounting bracket, on the right side, bolts through the carpet. *The actual buckle assembly doesn't look like the one shown in the figure.

 

Actually the seat belt buckle is bolted down to the bracket underneath the carpet and the belt comes out from a slit on the carpet.

 

The two M8 x 24mm flange bolts to mount the front brackets are 1409900317, but the tip of the bolts are narrow and not threaded. Only 20mm of 24mm is threaded. If you can't find 24mm or 25mm, 20mm or 18mm should work just fine.

 

Cataloging the base trim covers for the center seat.
They all came from the Mercedes Parts facility in Vance, Alabama and all made in US.
The production dates varies, and some are from 2007.



25192010868k67 Front narrower trim cover, Buckskin(Tan) Production Date Aug. 30th 2007.



25192012868k67 Rear wider trim cover, Buckskin(Tan), Production Date Sep. 7th 2007.



25192012869051 Rear wider trim cover, Black, Production Date Oct. 2nd 2008.



25192010869051 Front narrower trim cover, Black, Production Date unknown, possibly 2011 or 2012. Revised new design.



25192012867e94 Rear wider trim cover, Gray, Production Date Sep, 10th 2007

Gray front trim 25192010867e94 has been discontinued, and should be replaced with Black 25192010869051 .

 

Thank you very much for this very informative thread. I am wanting to add the 7th seat to my 2011 R350. Is it the same for my updated model? I know that it is basically the same vehicle, but didn't want to get started and it not work properly. Also, does anyone know of a 11-12' middle seat for sale?

 

I have a 2008 r350 with the seat in the second row. I am looking to trade someone with a center console. Just message me if interested. Beige is the color