I've been lurking here for a few weeks while deciding what I wanted to replace my 2001 Jeep Grand Cherokee with. The 4Runner and Xterra were the finalists. Pulled the trigger on a 2013 SR5 a couple of days ago and now I'm ready to accessorize it. I saw a used one with chrome step bars and it looked great. Looking online, though, I'm confused about the difference in step bars and full length nerf bars with steps built in. Some manufacturers sell both and I don't see any difference in the two. Also, are there particular brands that fit or look better on the 4Runner? Can mud guards be used with step bars, or do they interfere? The online sites don't list bars for 2013 4Runners, but wouldn't the 2012 bars fit? Sorry for all the newbie questions. I'm sure they'll be more later.

I like the N-Fab nerf bars (just bought mine a couple weeks ago). There's quite a few people on here that have them. They don't fit on the SR5 straight out of the box, but there's a guy on here (RiDE) that makes a kit that allows you to put them on. I posted the link to his thread below.

http://www.toyota-4runner.org/showthread.php?t=107396

I can't answer your other questions.

Nerf bars (sliders) offer protection to your rocker panels while off roading. Step bars and running boards may deflect some road debris, but they offer little protection for off roading.
Check out Budbuilt, Shrockworks, or Metaltech 4x4. Any sliders listed for a 5th gen 4runner sr5 (2010-present) will fit. Things to watch out for would be sliders listed for the trail edition (different rocker panels, kdss lines) or for the limited (xreas). Also pay attention to whether they are bolt on, or require welding.

A few companies also offer deck plating and options like bump-outs. Lots to consider.

With some more search time on the forum (probably several days worth), you can find pictures and/or comments/reviews on most of the options available...at least on the "name brand" offerings.

If you are not planning on doing any off-roading, I highly recommend the Westin nerf bars. I just took off the platinum series oval bars and will be cleaning them up and posting pics to sell them in the next week. A new set will run you about $350 (minus whatever discount your website of choice is offering). Myself and Wonderbreadman have some good pictures in our Garage.

If you will be doing anything off-road or anything that you would be concerned with ground clearance, DO NOT get anything like the Westins. N-Fabs will be your next best option...although if you go the route of using the spacers to make them fit, your ground clearance still suffer greatly as with the Westins. In your searching on here you will see that some guys simply remove the rocker panels (like myself) or trim them so the n-fabs will fit without spacers. N-Fabs will run you $300-$330 depending on how you catch the discounts.

If you will be getting into more hardcore offroading, you will want to get rock sliders, rock rails, etc. Jono mentioned several manufacturers with this type of offering. You will find some that will mount with the SR5 rocker panels and some that you would have to remove or trim like with the N-Fabs. Any slider options will run you $450 for the basic offering and can get up to $650+ with powder coating and step plate options.

I am by no means an expert, but hopefully this helps. I was in the same boat you are about a year ago...I wish I has at least this much information before making any purchases! Saves a lot of money, time and effort to do it right and get what you want/need the first time. Good luck and happy modding.

I agree with the comments from FatTiresRollin and my choice was the NFab Nerf Steps. Mine went on a Trail, but they go on an SR5 with a little work, there is good info on how to trim the rocker panels at:

ANTMAN'S Thread

I did not lose any ground clearance, they are slightly above the frame rails. Part # T1064

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