Install Ebay winch for $370 on '97 3rd Gen 4Runner - no welding & stock bumper

[calnhob]

Update.

First of all, I must thank those that provided help warnings. I went out to check and sure enough, those end caps are held on my just two 1" bolts, maybe M8?

The end cap was definitely stretched. Removed everything and now it's back to the drawing board. At least nothing serious occurred while it was on.



Hi All,

I just installed an Ebay winch this weekend and thought I'd share the process and parts. This is for the 97 which has a different bumper than the 98-02.
Winch is rated for 13K lbs with a 12K lbs synthetic line. Tested on some trees and it worked great but need to test it for reals on the trail.

Winch is mounted to a HF universal winch mount which needed some cutting but no welding. I used Steel strut channels and 4 square washers to lower the winch so it would fit under the chrome bumper. It's all held in place by two 1/2" x 6" grade 8 bolts.

Total weight is about 95 lbs (60 lbs winch / 25 lbs winch mount / 5 lbs hardware). Lowered my truck about by 1/4".

1. X-Bull Winch 13K lbs/ 12K lbs synthetic line - Ebay $260.00
   Amazon link showing detailed pics https://www.amazon.com/X-BULL-Synthetic-Electric-Winch-Capacity/dp/B01FU5QL1Q
2. Universal Winch Mount - HF $45.00
3. 12-Gauge Electro-Galvanized Half Slot Steel Strut Channel - HD $21.00
4. Heavy Duty Bolt on D-Ring,Clevis - Ebay $30.00
5. 2 x 1/2-13" x 6" Grade 8 Hex Screws & washers $6.00
6. 5 pack Superstrut 1 hole 1/2" square washer $5.00
7. 4 x 3/8" x 2" Grade bolts for the D-Ring $4.50

This shows the two cuts that has to be made on the ends of the mount to fit under the frame

Bolting and spacer details.

Some glamour shots around the island.

 

[calnhob]

Only really concern I have are the two bolts holding everything on the frame but they are grade 8 coarse thread (Grade 8 bolts have a tensile strength of 150,000 pounds per square inch). Wish I could weld it on but don't have access to a welder or know how to weld. Might add some more bolts for added security later on.

 

[csp]

So only two bolts attach the winch plate to the frame, with unitstrut as a spacer between them?

So many things wrong with this install from a strength standpoint. Luckily it's heavy enough that when it does rip free from the frame it won't travel far.

I'm not trying to beat you up, but this is a case of just because you can doesn't mean you should.

 

[T4R2014]

Sketchy but at least looks clean. People plate that end of the frame for a reason. Those factory frame ends are for pushing, not pulling. I’d redo it tbh. Not hating on you but I wouldn’t want you to damage your truck.

 

[bmodo16]

Not secure at all man. The bolts that hold those end caps are not very big, nor strong. This is asking for trouble...

 

[thecole1098]

Mine was done the “proper” way by welding the HF plate to the frame directly and using a multitude of grade 8 bolts to reinforce the plate to the frame as well as 4 bolts that are used just to attach the winch to the plate. It also makes it so I don’t have to cut out the entire plastic section of the bumper like you did.

 

[Scramble]

Only really concern I have are the two bolts holding everything on the frame but they are grade 8 coarse thread (Grade 8 bolts have a tensile strength of 150,000 pounds per square inch). Wish I could weld it on but don't have access to a welder or know how to weld. Might add some more bolts for added security later on.

Just think about this logically for a second. Say you were winching yourself up a hill. Do you really trust 2 bolts to hold the weight of a 4Runner?

 

[4Runner4Leon]

Like others said, that is one heck of a bending load on those two long bolts. Bolts don't like bending, try to keep them in tension or shear.

You can do some basic calcs to see how much margin you have, but I am guessing it'll be zero to none.

 

[thecole1098]

Just think about this logically for a second. Say you were winching yourself up a hill. Do you really trust 2 bolts to hold the weight of a 4Runner?

Not only that, but it doesn’t help that those two bolts are mounted to something that isn’t designed for weight in the first place. Also, it would help if the bolts were flush to what they are attached to, otherwise the bolt head could just bend when under tension. Even though they are grade 8, this could most certainly cause them to snap.

 

[theesotericone]

Like others said, that is one heck of a bending load on those two long bolts. Bolts don't like bending, try to keep them in tension or shear.

You can do some basic calcs to see how much margin you have, but I am guessing it'll be zero to none.

Not only that, but it doesn’t help that those two bolts are mounted to something that isn’t designed for weight in the first place. Also, it would help if the bolts were flush to what they are attached to, otherwise the bolt head could just bend when under tension. Even though they are grade 8, this could most certainly cause them to snap.

I'll bet you the frame rail end caps break off before the bolts shear. Who's in?

OP, that might hold for winching off a telephone pole on the street but it will fail sooner rather then later.

 

[phattyduck]

Those frame horns are held on by much smaller bolts than those SAE bolts you used. Properly torqued, those 1/2" bolts should have crushed those cans on the front. I wouldn't trust the uni-strut in the orientation either - it creates lots of force in the weak direction of the u-channel.

If you are going to bolt something on, use the factory tow strap bolt locations and an extra through-bolt right behind those frame horn caps (drill for a 3/8" bolt). That will give you 4 M10 (edit, may be M12) bolts and 2 3/8" bolt, spreading the load across some length of the front of the frame.

-Charlie

 

[calnhob]

Updated original post.

 

[4Runner4Leon]

Just for giggles and a sanity check, tensile stress in a bolt in bending is

σ = 32 * Mb/πd^3

So if we assume that the bolt max strength is 150,000 psi, and 0.5" dia, then the max moment you can apply to it is:

Mb ~ 12,000 in-lbs.

If we simplify and assume that the whole 6 inches of the bolt is in bending, then the max load you can apply to each bolt is:

F = Mb / 6 = 2,000 lbs.

So for two bolts, probably 4,000 lbs total load, give or take 2,000 lbs .

I know that this is conservative since the bolt is not in pure bending, especially if it's properly preloaded - OTOH, I haven't used any safety factors or reduced max stress area due to threads. I'd guess the two are more or less a wash.

So I don't think you have anywhere near the capability to pull a 5,000 lb load with this. You can probably get a 4Runner to roll, but if it's stuck in a rut or mud, parts are going to break, and it's not going to be pretty.

All this aside from the fact that like others said, the bolt attach point is not strong enough to begin with.

Be careful with this setup.

 

[4Runner4Leon]

Mine was done the “proper” way by welding the HF plate to the frame directly and using a multitude of grade 8 bolts to reinforce the plate to the frame as well as 4 bolts that are used just to attach the winch to the plate. It also makes it so I don’t have to cut out the entire plastic section of the bumper like you did.

I've been meaning to ask, do you have a description of your setup somewhere?

 

[Fern]

Since you have it where you want it, I would get some steel plate. Cut the plate into sections so you can just take the pieces to a shop to weld it on for you. Should only take a couple hours of shop time.

 

[theesotericone]

snip:Science stuff:snip

Be careful with this setup.

So your gonna leave out the sheer strength calcs? lol

 

[4Runner4Leon]

So your gonna leave out the sheer strength calcs? lol

Hehe, yup - 1/2" Grade 8 bolts can take 17,000 lbs in shear. Each.

 

[thecole1098]

I've been meaning to ask, do you have a description of your setup somewhere?

Unfortunately, no I never got around to doing a write up of it. It's times like that where I wish I actually had a build thread already going. I suppose it's not too late however as I still plan on modding it for quite some time. I PM'd you back earlier, so if you want to know more, just let me know.

 

[4Runner4Leon]

Unfortunately, no I never got around to doing a write up of it. It's times like that where I wish I actually had a build thread already going. I suppose it's not too late however as I still plan on modding it for quite some time. I PM'd you back earlier, so if you want to know more, just let me know.

Yes please, I am seriously considering a front winch setup, and yours looks great! Just a few clear pictures will probably be enough, and then I can ask you questions here and there. Thanks!

 

[Scramble]

Unfortunately, no I never got around to doing a write up of it. It's times like that where I wish I actually had a build thread already going. I suppose it's not too late however as I still plan on modding it for quite some time. I PM'd you back earlier, so if you want to know more, just let me know.

Do it! I started my thread a year after my build started & i'm still behind at July of 2016. LOL