When EMD designed the cabless DD35, the intent was to use a GP35 (or any cab equipped locomotive) as the lead. There was concern about "nosing", the tendency for such a large rigid wheelbase locomotive to go straight when it encountered curves in the track, thus realigning the track. The track standards were better on the UP than some other railroads, and the problem did not materialize. So the UP asked EMD to install cabs on the next batch of 15 DD35's, and by the time of the order, EMD had some 645 prime mover equipped SD40's in field testing, so the DD35A's got the same flared radiators as the test units. UP DD35A 82 was equipped for Radio Control (RC) operation in May 1968, serving as the control unit, matching UP #82B which served as the remote. All radio control equipment was removed from both units during July 1973 at Salt Lake City, Utah.