BakFlip MX4 Install Tips

I just installed the BakFlip MX4 Tonneau Cover on my 2020 Tacoma Off-Road Short Bed. I watched a number of videos and looked through this forum to see how others did their install.

If you are looking to install this cover here is a recap of the best video I found along with a couple of suggestions or tips to help you out.

Install Video: Extreme Terrain Toyota - Youtube - "Tacoma BAK Industries BAKFlip MX4 Folding Tonneau Cover (2016-2019) Review and Install - Link: https://www.youtube.com/watch?v=fbi41Yp0_IY

Additional Tips:
1 - When you are putting the side rails on, check the gap between the front edge of the top bed rail and the side rail edges. If there is a gap you should add some weather stripping or rubber to ensure there is no gap. This will help to minimize any water getting in from that area.
2 - Side Rail Brackets - The brackets used to attach the side rails are aluminum, but everything in the bed is black, so I spray painted the brackets with bumper coat black paint.
3 - Side Rails - Many people say that water leaks in from the sides and to put a small bead of silicone along the length of the rails. I forgot to do this, but it can't hurt. If mine leak, I'll take them off and apply the silicone.
4 - Drain Hose - Most videos skip how they ran the drain hose. Here is what I did. I bought two rubber grommets (1-1/8OD x 23/32ID) from Lowes and used a 7/8" spade drill bit to drill the holes in the front of the bed. I cut the hose to length and then put the smooth finished end through the grommet and the edge I cut I connected to the bed cover fitting.

I have the older BakFlip G2 on a previous truck that I kept for 12 years. It had some wear and tear, but was still holding up after 12 years. The MX4 is an improvement over the G2 so I don't see why it won't last just as long.

 

Got mine installed today.

 

Looks great, did your truck come with the power tailgate lock? That's my next purchase (Toyota Part No:

$162 PK3B6-35JS0 Toyota Genuine 2019 & Newer Tacoma Short Wheelbase Tailgate Lock (PK3B6-35JS0)

PK3B6-35JS0)

 

No, but I ordered one back in November for my long bed and they installed it before Christmas. So I’m good to go now.

 

Have you had any issues with the rails dropping slightly while closing the final panel when the tailgate is up? Mine sometimes push down so the latches can't engage, unless I open the tailgate or press really hard on the top. Not sure if I need to adjust something.

 

i don’t have that problem with mine and it’s only a month old. You might be out of square just a little.

 

I had this issue where I had to either force it to lock closed or open the tailgage to close. Once I put in total chaos bed stiffeners it closes with out any issues

 

Mine leaks on both sides of the tailgate. There is about 1/4" gap on both sides of my tailgate. I am not to concerned as it only leaks a bit on the back of the bed mat.

 

I have to drop the final lid with a little force to get the latches to catch when the tailgate is up. If I open the tailgate the final lid closes normally. I'm chalking it up to it being brand new and the rubber seals that come down on the tailgate are still hard from the cold. If it continues to do it I'll try and move the entire cover a little closer to the cabin. This should provide less rubber to hit on the tailgate and I expect it will close easier. Can't go to far or it will leak. My previous BakFlip also leaked on both sides of the tailgate. Never gave me much of a problem.

 

Installed mine a few weeks ago. Purchased used from an local member for $200

very happy

 

Great tips! I like your drainage hose method better than the other configurations out there.

I just bought my MX4 yesterday on Amazon. Got it for 25% off then the price went back up to $999. Not sure if it's because it's open-box or what. I'll find out when I get it tomorrow.

 

After the first rain, I found that the side rails allowed water in on both sides. This is because the bed rails are not smooth and the rubber seal from the BakFlip can only keep so much water out. I took the rails off and put a bead of Black RTV along the rails. Put everything back on and a few days later I went through an automatic car wash. Not even a drip of water came in from the front or sides. The only water came from the gap in the tail gate corners which is expected. Time will tell if the RTV keeps the seal or breaks loose do to vibration. Overall, extremely happy with the MX4.

 

That's a great price! I paid $995 for mine. I really like this cover and low height profile.

 

Two Yutes:
I just got my cover delivered today and will install it this weekend. I cannot visualize why you would have to take the bed rail off to apply the RTV. Can you send a picture of what you did?

 

Jack-Didley, you don't have to take the bed rail off. I put on the BakFlip hoping it wouldn't leak. It did so I took the BakFlip off and applied a bead of RTV on the underside of the BakFlip rails and then put the BakFlip rails back on the truck and put the cover back on. The picture below shows that I put RTV on the BakFlip both side rails as well as under the top header. It just helps the weather-striping do its job better.

Now, understand that without the RTV the BakFlip leaked, but it wasn't terrible and if you don't mind some water getting in then you don't have to apply RTV or your adhesive/caulking/gasket material of choice. For me, I had a BakFlip on a previous truck and the only place water got in was near at the tailgate on both sides where there is a gap. This is expected, it isn't waterproof and there is nothing you can do about that. I wanted my bed to stay 99% dry, so I applied the RTV. Now that I applied the RTV the only place water gets in is again at the tailgate on both sides because of the gap.

 

I went the foam weather stripping route and have had no leak.

 

I thought about foam, but wasn't sure if it would get water logged and then leak so I decided on RTV. If I had know someone had used foam and it worked, I would have used it since it is much easier to use and easier to take off if ever needed.

 

I never put drain hoses on mine. I don't see much water in the bed when it rains but then again I live in Socal.

 

I drilled the front of the bed and routed my hoses there above the wheel wells. Nice and short and out of the way