Nothing Special Posted December 29, 2023 Share Posted December 29, 2023 ... mount them to the bottom of the frame rail? At most would need to drill 2 holes to mount and I think I would use something like a large flat washer to spread the load over a larger area on the inside of the frame. Dave ---- I think my '95 F-150 had a crumple zone in the frame right where you'd want to mount tow hooks. I remember seeing that there was no flat part of frame anywhere I could've mounted them. But that was a '95. I have no idea when Ford added that crumple zone. In my case I added a front receiver so that gave me a recovery point and I didn't need to worry about tow hooks anymore. Link to comment Share on other sites More sharing options...
JimJam300 Posted December 29, 2023 Share Posted December 29, 2023 I have not looked at my F100 4x2 but I cant see why you cant get hooks that even have the keeper tab so what ever is on the hook will not come off and mount them to the bottom of the frame rail? At most would need to drill 2 holes to mount and I think I would use something like a large flat washer to spread the load over a larger area on the inside of the frame. Dave ---- You can get aftermarket hooks that are the same style for much, much cheaper. Maybe they even bolt up the exact same. If you don't have the holes drilled, then even better. $10 on Amazon EDIT Sorry Dave I didn't mean to respond to your exact message haha. It was the last one on the page and I hit reply. Link to comment Share on other sites More sharing options...
CDLong Posted December 29, 2023 Author Share Posted December 29, 2023 ... mount them to the bottom of the frame rail? At most would need to drill 2 holes to mount and I think I would use something like a large flat washer to spread the load over a larger area on the inside of the frame. Dave ---- I think my '95 F-150 had a crumple zone in the frame right where you'd want to mount tow hooks. I remember seeing that there was no flat part of frame anywhere I could've mounted them. But that was a '95. I have no idea when Ford added that crumple zone. In my case I added a front receiver so that gave me a recovery point and I didn't need to worry about tow hooks anymore. I thank everyone for your help. Tow hooks are on the way. I'll post what i do to get them moumted. I'm still found of the hitch mounted behind the bumper. Link to comment Share on other sites More sharing options...
CDLong Posted February 9 Author Share Posted February 9 I thank everyone for your help. Tow hooks are on the way. I'll post what i do to get them moumted. I'm still found of the hitch mounted behind the bumper. I have the tow hooks. It appears they need to be 3 inches lower than the frame. My question is what should I should use for a spacer? 2 pieces of 1 inch square tubing 3 inches long per side or 1- 3 inch square tubing per side? Grade 8 bolts? Link to comment Share on other sites More sharing options...
Nothing Special Posted February 9 Share Posted February 9 I have the tow hooks. It appears they need to be 3 inches lower than the frame. My question is what should I should use for a spacer? 2 pieces of 1 inch square tubing 3 inches long per side or 1- 3 inch square tubing per side? Grade 8 bolts? Keep in mind that using spacers stresses the bolts much differently. With the tow hook attached directly to the frame the bolts are in shear. That means you are basically trying to cut through the bolt, with the hole in the frame and the hole in the tow hook being the two sides of the scissors that are trying to do the cutting. Bolts are good at resisting this. When you put a 3" spacer between the hook and the frame you are now trying to bend the bolt rather than shear it, and they bend a lot easier than they shear. So anything you can do to hold the head of the bolt back will help reduce the stress on the bolt. Just looking at the spacer, what you want to do is keep the spacer from collapsing, which would effectively loosen the bolt. So a piece of 3" square tubing laid on its side wouldn't be the best option since the tubing could collapse in on itself. A single sleeve on each bolt would be best at preventing the spacer from collapsing, but that would be much worse than the 3" tube at helping to hold the heads of the bolts back. A solid 3" spacer would be good (but heavy). Or sleeves welded into the 3" tube. Link to comment Share on other sites More sharing options...
CDLong Posted February 9 Author Share Posted February 9 Keep in mind that using spacers stresses the bolts much differently. With the tow hook attached directly to the frame the bolts are in shear. That means you are basically trying to cut through the bolt, with the hole in the frame and the hole in the tow hook being the two sides of the scissors that are trying to do the cutting. Bolts are good at resisting this. When you put a 3" spacer between the hook and the frame you are now trying to bend the bolt rather than shear it, and they bend a lot easier than they shear. So anything you can do to hold the head of the bolt back will help reduce the stress on the bolt. Just looking at the spacer, what you want to do is keep the spacer from collapsing, which would effectively loosen the bolt. So a piece of 3" square tubing laid on its side wouldn't be the best option since the tubing could collapse in on itself. A single sleeve on each bolt would be best at preventing the spacer from collapsing, but that would be much worse than the 3" tube at helping to hold the heads of the bolts back. A solid 3" spacer would be good (but heavy). Or sleeves welded into the 3" tube. Thank you Bob. How about a 3 inch solid aluminum block? Link to comment Share on other sites More sharing options...
Nothing Special Posted February 9 Share Posted February 9 Keep in mind that using spacers stresses the bolts much differently. With the tow hook attached directly to the frame the bolts are in shear. That means you are basically trying to cut through the bolt, with the hole in the frame and the hole in the tow hook being the two sides of the scissors that are trying to do the cutting. Bolts are good at resisting this. When you put a 3" spacer between the hook and the frame you are now trying to bend the bolt rather than shear it, and they bend a lot easier than they shear. So anything you can do to hold the head of the bolt back will help reduce the stress on the bolt. Just looking at the spacer, what you want to do is keep the spacer from collapsing, which would effectively loosen the bolt. So a piece of 3" square tubing laid on its side wouldn't be the best option since the tubing could collapse in on itself. A single sleeve on each bolt would be best at preventing the spacer from collapsing, but that would be much worse than the 3" tube at helping to hold the heads of the bolts back. A solid 3" spacer would be good (but heavy). Or sleeves welded into the 3" tube. Thank you Bob. How about a 3 inch solid aluminum block? I'm not an expert, but I don't think I'd use aluminum. First is aluminum and steel don't play well together in a corrosive environment. Maybe not an issue if you live in the desert, but here in the rust belt it would end up being impossible to disassemble after a couple of winters. Also aluminum isn't as strong as high grade bolts, so I'd be concerned about it possibly yielding under the stress, causing the bolts to loosen up. On the bolt grade, I'm not sure if 5 or 8 would be better. 8 is stronger, but 5 is tougher (it can take a harder hit without breaking). I think I'd use grade 8, but I'm not saying that's the RIGHT answer. Link to comment Share on other sites More sharing options...
ArdWrknTrk Posted February 9 Share Posted February 9 Also aluminum isn't as strong as high grade bolts, so I'd be concerned about it possibly yielding under the stress, causing the bolts to loosen up. On the bolt grade, I'm not sure if 5 or 8 would be better. 8 is stronger, but 5 is tougher (it can take a harder hit without breaking). I think I'd use grade 8, but I'm not saying that's the RIGHT answer. Any Tractor Supply has either one by the pound... 5 is not only 'tougher' but FAR less prone to corrosion stress cracking. It won't as readily provide nucleation sites for cracks to get a beachhead. Aluminum may* not"play well" with iron & steel, but we see steel fasteners in aluminum everywhere. Cylinder heads, transmissions, bellhousing, transfer cases, water pumps, etc. I think the bigger issue may be it's modulus of elasticity and that it might deform under the head when subject to something more than pure clamping load. OTOH, it won't budge until this happens and it may help absorb some shock that would otherwise cause failure in a thread root or the part the hook is bolted to. If it does this, it's sacrificed itself to save the vehicle (and it isn't possible to be a catastrophic incident, like Jonathan outlined last year) Just my 2ยข Link to comment Share on other sites More sharing options...
Gary Lewis Posted February 9 Share Posted February 9 I'm not an expert, but I don't think I'd use aluminum. First is aluminum and steel don't play well together in a corrosive environment. Maybe not an issue if you live in the desert, but here in the rust belt it would end up being impossible to disassemble after a couple of winters. Also aluminum isn't as strong as high grade bolts, so I'd be concerned about it possibly yielding under the stress, causing the bolts to loosen up. On the bolt grade, I'm not sure if 5 or 8 would be better. 8 is stronger, but 5 is tougher (it can take a harder hit without breaking). I think I'd use grade 8, but I'm not saying that's the RIGHT answer. I agree with all you said, Bob. Further I'd use bolts that are a tight fit in the holes in the frame, spacer, and hook. That will keep twisting to a minimum. As for the bolts, G8's have a higher torque spec, and I'd tighten them to that spec. That will give the maximum friction between the parts. Link to comment Share on other sites More sharing options...
ArdWrknTrk Posted February 9 Share Posted February 9 Also aluminum isn't as strong as high grade bolts, so I'd be concerned about it possibly yielding under the stress, causing the bolts to loosen up. On the bolt grade, I'm not sure if 5 or 8 would be better. 8 is stronger, but 5 is tougher (it can take a harder hit without breaking). I think I'd use grade 8, but I'm not saying that's the RIGHT answer. Any Tractor Supply has either one by the pound... 5 is not only 'tougher' but FAR less prone to corrosion stress cracking. It won't as readily provide nucleation sites for cracks to get a beachhead. Aluminum may* not"play well" with iron & steel, but we see steel fasteners in aluminum everywhere. Cylinder heads, transmissions, bellhousing, transfer cases, water pumps, etc. I think the bigger issue may be it's modulus of elasticity and that it might deform under the head when subject to something more than pure clamping load. OTOH, it won't budge until this happens and it may help absorb some shock that would otherwise cause failure in a thread root or the part the hook is bolted to. If it does this, it's sacrificed itself to save the vehicle (and it isn't possible to be a catastrophic incident, like Jonathan outlined last year) Just my 2ยข Bill, would probably offer some good advice here, after all the testing he's done at Newport News. Link to comment Share on other sites More sharing options...
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