Merge SS1 & SS2 into SS3 by latest date

[SocLost]

I'm fairly new to excel and need some help. I need to merge the entire row from SS1 and SS2 into SS3. Simple enough but if an item in SS2 column A matches an item in SS1 column A and the date in SS2, column D is newer than SS1 column D, then copy then merge the row from SS2 into SS3 and on thru the list. There are several thousand items in SS1 and a few hundred in SS2 and all items need to end up in SS3 (latest dates) without duplicates. I've tried match and vlookup but can't seem to get the date part, I think I get it right but then find duplicates or the wrong date. Here's what I'm working on, please help if you can spare the time. I'm probably copying and pasting these wrong but here goes. Many Thanks in Advance!

SS1 Lot Qty Status Expires AIV260 827 full 10/24/2014 AIV261 872 full 1/31/2014 AIV262 358 45% 10/25/2014 AIV263 818 full 9/10/2014 AIV264 883 full 1/31/2014 AIV265 908 full 9/15/2014 AIV266 818 full 10/18/2014 AIV267 834 full 10/23/2014 AIV268 798 full expired AIV269 25 3% 10/25/2014 AIV270 807 full expired AIV271 781 98% 10/10/2014 AIV272 1077 full expired AIV273 1337 full expired AIV274 2075 full AIV275 2433 full expired AIV276 2305 full tbd AIV277 1368 full expired AIV278 869 full expired <tbody> </tbody>
SS2 Lot Qty Status Expires AIV261L4 832 full 5/9/2015 AIV264L4 838 full 5/16/2015 AIV268L4 840 full 11/10/2014 AIV285L4 831 full 11/23/2014 AIV306L3 800 full 7/8/2015 COL011L4 836 full 5/27/2015 COL013L4 921 full 11/10/2014 COL014L4 1135 full 11/9/2014 ERP016L4 906 full 1/3/2015 ERP025L4 828 full 5/30/2015 ERP026L4 913 full 5/4/2015 ERP027L4 1059 full 5/5/2015 ERP028L4 851 full 12/26/2014 ERP029L4 887 full 11/19/2014 IMG001L4 802 full 1/1/2015 LS1010L4 839 full 5/6/2015 LS1011L4 831 full 5/11/2015 LS1013L4 33 0.10% 10/8/2015 LS1015L4 978 full 5/9/2015 <tbody> </tbody>
Final Results in SS3 Lot Qty Status Expires AIV260 827 full 10/24/2014 AIV261 832 full 5/9/2015 AIV262 358 45% 10/25/2014 AIV263 818 full 9/10/2014 AIV264 838 full 5/16/2015 AIV265 908 full 9/15/2014 AIV266 818 full 10/18/2014 AIV267 834 full 10/23/2014 AIV268 840 full 11/10/2014 AIV269 25 3% 10/25/2014 AIV270 807 full expired AIV271 781 98% 10/10/2014 AIV272 1077 full expired AIV273 1337 full expired AIV274 2075 full AIV275 2433 full expired AIV276 2305 full tbd AIV277 1368 full expired AIV278 869 full expired AIV285 831 full 11/23/2014 AIV306 800 full 7/8/2015 COL011 836 full 5/27/2015 COL013 921 full 11/10/2014 COL014 1135 full 11/9/2014 ERP016 906 full 1/3/2015 ERP025 828 full 5/30/2015 ERP026 913 full 5/4/2015 ERP027 1059 full 5/5/2015 ERP028 851 full 12/26/2014 ERP029 887 full 11/19/2014 IMG001 802 full 1/1/2015 LS1010 839 full 5/6/2015 LS1011 831 full 5/11/2015 LS1013 33 0.10% 10/8/2015 LS1015 978 full 5/9/2015 <tbody> </tbody>
Many Thanks for any assistance.

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