If getting lag bolts into the post is an issue due to cracking - you could put a backer plate on the other side and use standard bolts/nuts and sandwich the post between two pieces of metal.

Agree with the above - you need a diagonal on that - and/or some wheels.

Here are some pics of my gates. The smaller one is about 5' wide. The big one is 10' and has two of the metal frames inside it. It's super heavy since it's two sided, the back side looks like the front.
http://forums.pelicanparts.com/uploa...1677189203.JPG

http://forums.pelicanparts.com/uploa...1677189203.JPG

http://forums.pelicanparts.com/uploa...1677189203.JPG

http://forums.pelicanparts.com/uploa...1677189203.JPG
If you're going to be rebuilding your gates I highly recommend you get some of the adjustable frames for them. You could put new 2x4's on the frames and reuse the existing outer wood so they wouldn't even change looks.

http://forums.pelicanparts.com/uploa...1677193265.jpg
http://forums.pelicanparts.com/uploa...1677193265.jpg
Chris, here's a couple of gates I built years ago. Had to replace some rotten boards on the garden gate today. As you can see I used gate guy wires with turn buckles. You must with a wooden gate or it will sag. Sorry to say but whoever built your gates shouldn't build gates. I would build new ones. Even with wheels those gates will never close together parallel. A steel or aluminum frame and the gate is stable forever. You can use the existing posts they're fine. The top right hinge has been moved down because of the split in the post but an extra long hinge bent in the vise to wrap around the back of the post will work fine.

http://forums.pelicanparts.com/uploa...1677194125.jpg
http://forums.pelicanparts.com/uploa...1677194125.jpg
Your gate opening looks like a drive through 8'. This is a 21' drive through gate I built out of square steel tube. It's a sideways roller. Works much better than a swing roller. You've been to my house and I'm sure you saw this gate, it works if you have retraction space past the post

Sadly, after looking at those pics I think the OP's gate is a do over. The posts can be saved but the hinges will never carry the weight without wheels and it is always going to be a wobbly mess. A good Saturday project and with a little engineering and not too much $$ it will turn out great.

Looks like we got fresh fire wood for a beach party though.

I wish I had space for a sideways roller, Greg. I only have a long, 10’ wide driveway unfortunately.

It’s definitely going to be a good, couple of days worth project. Lots of great ideas here. You guys never cease to amaze me. Hoping for good weather soon but I’m not going to complain if it keeps raining here in Northern CA.

How are your 1x6's attached to the 2x6's?
Nails or screws?

If I were building my small gate from scratch I would have put the hinges in line with the bars of the frame. I actually replaced my gate and used the frame on the replacement. I didn't want to move the existing holes in the pole for the hinge pins, thus they didn't end up lined up with the cross bars. Would have been a lot stronger if I'd been able to do that.

Nails, not screws

They look like you could save them if you want to rebuild the frames.

Yes they’re in good shape

As I see it, the problem with your gates is that the hinges need to be in perfect alignment in order for them to not put a twist into the plane of the gate. Using the hinges like mine would help in that they don't do that. The bottom hinge supports the weight and top one is used to align the tilt. Get some of those adjustable steel frames and go to town on the garage floor. That's where I built mine since it's the most level concrete I have. Took me about 4 hours to remake my gate when I had to replace it due to TERMITES eating the boards. My brother's-in-law built my first gate as I was working on the fence. Getting the steel frame saved my bacon as it's easy to get it right. Once you get the hinges hung the face boards go right on.

The gate is bit twisted (you think?) and the question is which one? My plywood method will keep it square for a long time. Use a turn buckle to pull the twist out or keep the gate from twisting again with a block in the middle to straight it back up (run 2x4 across the middle of the gate on its back side) if necessary. The split can be fixed with a clamp and glue or simple drive a couple of lag bolts to keep it from spitting along with glue (pilot holes are necessary). Let it set up over night, plug holes with dowels and glue (it has some rot in those holes), drill out for through bolt, reinstall hinge in its original place. Gate removal isn't necessary to perform this task.

With gate attached, use shims and blocks to pick up gate near the center until the diagonals measurements are exact. Apply plywood along with glue and screw. Once that's done , you will discovered the gate will be super solid. I bet if you put your foot on one edge and pull on the gate, it will straighten right out. Its just tired.

If new gate are to be built, use a steel frame then attach wood gate on front to have the softer wood look. I normally use strap hinges only because they can be adjusted. If you want simple, build gate with 2x4 then attach plywood on the back side to keep gate from sagging in the future. Forget turn buckles and metal corner braces. Think of a shear panel wall is what you are creating.

Unfortunately, I should not have had a solid gate to begin with because of the gusts we get here sometimes. I think that’s part of the reason why the gate is all jacked up.

If you drill a hole on concrete and put a gate Cane bolt on the bottom of your gate, it keeps the wind from racking the gate. https://www.homedepot.com/p/Everbilt-18-in-Black-Heavy-Duty-Lockable-Cane-Bolt-20504/203561805

I have that but only on one of the doors when both should’ve been secured to the concrete when closed.

Issue with that it make it impossible to open from the outside. If this is a gate that doesn't require daily use, then you can get away with have both. Now you can install another latch near the bottom, say 2- 3' off the ground and attach a string to it through a hole so it can be open from the outside. These are quick and easy fixes to save on the trouble and expenses of having to make a new gate. If a new gate is a must, then it can be engineered differently with the known issues such as wind.

No, the reason it's jacked up is because they (the gate panels) don't have the structural integrity to stand up to the twisting induced by the winds. They need the diagonals added to do that.
My first small gate was all wood, including the diagonal. When it lost its integrity via the termite issue it started to have problems. I never thought I'd have to ever replace that gate in my lifetime. I was wrong. This gate will outlast me I'm pretty sure.

Do you have a skill saw or other means of cutting a sheet of plywood?

If so, you can fix this simply by cutting some 45* triangles out of a sheet of plywood. One 4'x8' sheet cut in half twice, ie quartered, will do it. You can get those cuts made at the store (Home Depot or Lowes) for @$0.50 a cut, last time I checked. Then once you get it home all you need to do is cut each piece once on the diagonal to get the triangles.
Glue/screw one edge of each triangle to the vertical sides of the corners. Shim the gate panels square using blocks to hold them in position and do the same along the horizontal edges of the triangles. This assumes you've taken care of making the hinges capable of holding the gates up.

Good advice from Scott with the gussets.
Also take the gates off and do this on a flat surface and make sure it is square before screwing them in. You said it is made with nails? lol Put a pile of screws in this bad boy.
Then better hinges and some wheels.

There are diagonals but maybe not installed right?http://forums.pelicanparts.com/uploa...1677259554.jpg

Generally I've seen them from the upper hinge to the lower corner. I think those are backwards. Look at the orientation of the turnbuckles above.

Maybe try the opposite diagonal on the back?

No, those are not backwards.

Wheels are not needed either.

THis needs to be addressed.

http://forums.pelicanparts.com/uploa...1677182105.jpg

Then the twist.

This

http://forums.pelicanparts.com/uploa...1677259554.jpg

has the diagonal in compression. (perfect for wood.)

A tension cable going the other way can be added (strategically) to counter the warping.

http://forums.pelicanparts.com/uploa...1677262501.jpg
I'd first open the gates and added some big lag screws at the locations marked in white.
Countersink/screw the heads in so they won't interfere with the closing gap.

Back to this (edit ^ yep ^ but more screws up top.)

http://forums.pelicanparts.com/uploa...1677182105.jpg

Screw and glue (epoxy or urethane)

Use a bunch of 3" $10 SS decking screws going in perpendicular to the hinge mount screws (don't let them interfere.)

Then move the hinge back up top. But get bigger hinges. Some that allow the hinge screws to be further back on the post.

Then I'd jack up the panels so they're squared up and put some deck screws into the existing diagonals.
If the existing hinges are still presenting a problem at the post attachments I'd remove the screws and thru bolt them into place adding a backer/doubler on the far side to really squeeze the post.

Maybe

http://forums.pelicanparts.com/uploa...1677260608.JPG

You can see how these will move the post mounting holes farther back.

I will also point out that 'over closing' the gate can rip hinges off like that.

The gate is a really long lever arm that carries some inertia with it on closing.

If the only 'stop' is at post, some big forces can be applied to those hinge mounts / the post.

Adding a small stop at the center, where the gates converge, would be smart.

Yup, the edge distance of the post mounting holes is what would be considered the weak link here. Not enough 'meat' in the post to support that weight.

http://forums.pelicanparts.com/uploa...1677264103.JPG
This type of hinge allows you to put the hinge pin almost in the middle of a 4x4 post.

Great ideas, fellas! Thanks a bunch.

Wish you were closer I'd offer to help. Buildin' stuff like this is great fun since I don't have to do it for a living.

Thanks Scott. I suck at building stuff but I’m willing to learn and since I’m retired, I have the time.

Plywood gussets on an outdoor gate? Are you guys using PT plywood? Even if it held up to sun and water I can't see how esthetically pleasing that gate would be

She's a real looker now. lol

Misc:
-Five or six latches per side.
-Metal turnbuckle rods on the surface to help keep square.
-Center stop per above.
-Add a row of self-latches between the gates. All attached with a single lift rod to tie top/bottom together.
-Add a drop-bar into pipe-hole both sides. They will also have those standard rotating forks to interlock.

-Full length heavy duty piano hinges. Super strong and ex$ensive. But if something goes wrong they will rip out the side posts before breaking.
-Inset metal arc wheel tracks (must be absolutely perpendicular to the post or it will tear it off). These are generally not a good idea because one little stone will stop it cold and the gate will flex over at the top with momentum.

-Single-piece lightweight gate .
-Folding closet-door linear style gate.

Wheels are another thing I don't like on swinging gates. Not only do they not work well but wheels are a remedy for crappy gate design.

The wheel thing won't work for my application, I don't think. My driveway slopes so when I open the gate, the wheel will hang unless it's on a spring mechanism and extend down to keep contact with the concrete.

Looking at this picture I can see that the driveway slope is acting as the gate stop. (poorly)

http://forums.pelicanparts.com/uploa...1677182084.jpg

I would be inclined (happy pun) to install an adjustable foot/stop on the inside of the gate, that would be the first thing to hit on closing. Adjust so each side stops at the same place and does not over close the hinges. ...or warp the gate.

Dragging that gate on the floor from it sagging is what make it twist like it. It just sagged over time and I bet it worked well when new. Shim to square it up, stiffen with plywood and you can get a lot more miles out of it. A little paint, it will all go unnoticed but you gotta to relocate that top hinge and get rid of that 2x. Squaring that gate is a breakfast burrito job and be done by noon and no beer needed maybe but just a couple of swear words to keep your man card. Good luck and let us know how it goes.