Mini Review of MB Cargo Box / Rails.
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From: Nashville
2017 S550 Iridium / Black Nappa, 2015 GL 550 Paladium Silver
Mini Review of MB Cargo Box / Rails.
Medium Cargo Box 13 cubic feet MB # 000-840-01-00 $625
Basic Carrier (Rails) MB # 166-890-13-93 $300
We opted for the MB model over Thule for the simple reason that we needed the box within 5 days and could not get the Thule unit within that time period. That said, I'm glad we went with the MB unit as in the end it cost me ~$100 more than getting the comparable Thule unit through Rack Attack with shipping. Rack Attack did not have the 13 cu ft unit in stock and said it would drop ship from Thule with a 10-14 day delivery time. The regional MB warehouse had the unit in stock and shipped to our local dealer in 2 days.
Fit / Finish is outstanding. We opted for the matte silver to match our iridium silver ML. The box has a slight carbon fiber look to it under the silver paint. Cool effect for sure. The rails are very nicely designed but a rather tight fit on the roof bars. So much that the SM thought the parts department ordered the wrong set. The back went on fairly easy but the front ones were a real bugger to get in place. The locking mechanism of the bars is a great design. The clamps act like a ratchet and click freely when you have reached maximum pressure by turning the small handle. The whole assembly has a high quality feel when using which was a pleasant surprise
Functionality is stellar and option of opening from either side is very handy. I loaded from a single side but midway through out trip needed something from the opposite side. Simple unlock / flip up, grab and go operation. The mechanism is pretty slick and works equally well from either side. This may be a standard feature for other boxes but this is the first one I've owned so wouldn't know. I should also share that most of the trip north was in heavy rain followed by temperatures in the 20's. The box was bone dry when we unpacked. However both locks were frozen shut when we went to repack a few days later. I had to use a hair dryer to thaw and spray WD40 directly into the lockset to displace the residual water. I need to find a better low temp lubricant to use on future trips north! The lock sets should really have some sort of rubber cap or something to prevent water from penetrating the cylinder.
Wind Noise is acceptable. Sure it makes some noise but I found that with the sunroof cover closed it was minimal. I also believe that the cabin of our ML so quiet anything out of the norm seems obtrusive. We had the box mounted back so that there was ~3" of clearance with the tail gate open. This put the front tip in line with the front side of the sunroof.
Cargo Capacity was more than enough for a family of four on an 8 day holiday trip. (The rear cargo area was filled with Christmas presents and our 85lb lab.) We picked up 4 cheap 24" duffle bags from WalMart @ $12 each vs the ~$300 MB branded box luggage. This left us with the front ~1ft for misc items.
Impact to MPG was minimal. We made the same trip at Thanksgiving without the box and averaged 21.6 MPG over 1300 miles. Average speed was 70MPH on highway with ~100 suburban miles. This trip with the box averaged 20.2 MPG over 1385 miles and total average speed of 55 MPH. This trip involved about ~200 suburban miles and a good bit of warming up in the mornings. Highway only return trip was 20.6 MPG with average speed of 69MPH - cruise was set at 80 MPH for 80% of trip.
Basic Carrier (Rails) MB # 166-890-13-93 $300
We opted for the MB model over Thule for the simple reason that we needed the box within 5 days and could not get the Thule unit within that time period. That said, I'm glad we went with the MB unit as in the end it cost me ~$100 more than getting the comparable Thule unit through Rack Attack with shipping. Rack Attack did not have the 13 cu ft unit in stock and said it would drop ship from Thule with a 10-14 day delivery time. The regional MB warehouse had the unit in stock and shipped to our local dealer in 2 days.
Fit / Finish is outstanding. We opted for the matte silver to match our iridium silver ML. The box has a slight carbon fiber look to it under the silver paint. Cool effect for sure. The rails are very nicely designed but a rather tight fit on the roof bars. So much that the SM thought the parts department ordered the wrong set. The back went on fairly easy but the front ones were a real bugger to get in place. The locking mechanism of the bars is a great design. The clamps act like a ratchet and click freely when you have reached maximum pressure by turning the small handle. The whole assembly has a high quality feel when using which was a pleasant surprise
Functionality is stellar and option of opening from either side is very handy. I loaded from a single side but midway through out trip needed something from the opposite side. Simple unlock / flip up, grab and go operation. The mechanism is pretty slick and works equally well from either side. This may be a standard feature for other boxes but this is the first one I've owned so wouldn't know. I should also share that most of the trip north was in heavy rain followed by temperatures in the 20's. The box was bone dry when we unpacked. However both locks were frozen shut when we went to repack a few days later. I had to use a hair dryer to thaw and spray WD40 directly into the lockset to displace the residual water. I need to find a better low temp lubricant to use on future trips north! The lock sets should really have some sort of rubber cap or something to prevent water from penetrating the cylinder.
Wind Noise is acceptable. Sure it makes some noise but I found that with the sunroof cover closed it was minimal. I also believe that the cabin of our ML so quiet anything out of the norm seems obtrusive. We had the box mounted back so that there was ~3" of clearance with the tail gate open. This put the front tip in line with the front side of the sunroof.
Cargo Capacity was more than enough for a family of four on an 8 day holiday trip. (The rear cargo area was filled with Christmas presents and our 85lb lab.) We picked up 4 cheap 24" duffle bags from WalMart @ $12 each vs the ~$300 MB branded box luggage. This left us with the front ~1ft for misc items.
Impact to MPG was minimal. We made the same trip at Thanksgiving without the box and averaged 21.6 MPG over 1300 miles. Average speed was 70MPH on highway with ~100 suburban miles. This trip with the box averaged 20.2 MPG over 1385 miles and total average speed of 55 MPH. This trip involved about ~200 suburban miles and a good bit of warming up in the mornings. Highway only return trip was 20.6 MPG with average speed of 69MPH - cruise was set at 80 MPH for 80% of trip.
Last edited by Pntblnk; Dec 29, 2013 at 10:09 AM.
