im a diesel mechanic and i never thought of spacers as a good idea, but my buddy told me about the german TUV and their testing that they do, so i went ahead and bought them from ECS (H&R 25MM) and i couldnt b happyer, they stayed perfectly torqued after the retorque period. 4.8is feels lil better in the turns after u turn the wheel over 30-40 degrees,


on the big trucks thers a spacers between Aluminum rims and iron drums and between the 2 aluminum rims, thats 3 all together just on one set of duallys, thats 6 non-metal spacers per axle, and they just float inbetween the rims... are DOT approved and never cause looseness and are made of a type of flexible hard rubber

the H&R 25mm spacers are very high quality material and the hub centric is spot on and the threaded inserts look good, IMO its the same as having a rim with a different offset