mtp9302

Hi all,

I have a 1999 Chevrolet Suburban LT that I am trying to install a trailer hitch on. The hitch is rated for 6000 lbs. without weight distribution and 10000 lbs with. I didn't think this would be too bad, but it is turning into one of the most frustrating things I've ever worked on. I know there are lot of very smart and experienced people on here, and I'm hoping someone can either give some good guidance on my latest debacle or tell me where to get it from.

I managed to fish all 6 bolt retainers and their bolts into the frame rails and the bolts are all sticking out of the holes in the frame, ready for the hitch. I'm not sure if this was supposed to be hard by design, but it sure was. I raised the hitch into position and found that the bolt furthest towards the front on the passenger side is in the hole crooked and will not align with the hole in the hitch. The other five are fine. The only thing I can guess as to the reason is that there is some piece of road debris that managed to lodge itself inside the frame, and it was where the bolt retainer went. Either that, or there is a raised point left over from a frame weld operation (not likely on the inside of the frame), in which case I'm pretty sure that's not going anywhere.

My guess is that I have two options. The first is to try and get the debris out and make the retaining plate lay flat. I tried the easy stuff like lifting the bolt head up and shooting compressed air through an access hole in the frame, jiggling the bolt and plate to try and get them sit flat, etc. These did not fix the problem. I have no idea how I would remove the bolt and/or retainer if that's what I have to do; I wrapped mechanic's wire around them and fished them through the frame to get them there. Any ideas?

I also thought of another option, which I need the experts here to either tell me is crazy or workable. I thought of slotting out the hole in the hitch so that the crooked bolt can come through as is. I suppose I could also do this to the frame, but the bolt is already in that hole so the hitch would be easier. I would probably need to slot it about 1/4". I understand that anytime a hole is put in metal a stress concentration results and reduces strength, but a 1/4" slot should not be noticeable from a towing capacity perspective, right? Another concern with this method is that I won't get as good a bite on a crooked retainer plate/bolt assembly. Is this a valid and substantial concern? The truck is rated at a 6000 lb towing capacity, so I would not exceed that. I'd also be removing some of the powder-coated surface; I'd probably use something like Rust-O-Lium to mitigate that corrosion risk.

Any and all help is appreciated; my first preference is to find a way to get the thing to lie flat, but I'm interested in what people think. I just can't seem to catch a break with this one. Sorry for the long post, and thanks.

old dog

the easiest way we used to do it in the shop i used to work in was to remove the bolt an spacer block and use a tapered reamer to make the hole straight (a drill bit would work) the right size 1/2 inch or 9/16 i don't know what hitch you have .most hitche's dont use wire to pull them through on the truck's i have done .

mtp9302

Thanks for the help old dog. The hitch is a Draw-Tite from eTrailer:

http://www.etrailer.com/pc-H~41511.h...icleid=1999479

Before I fished any bolts or retainers through, I did have to enlargen the existing holes in the frame; the one in question was opened up to 9/16". The hole itself is not crooked, and neither is the bolt. Rather, the bolt is going through the hole crooked. The bolt is a carriage bolt, and I am able to clock the bolt in the retainer's square hole (which is why I suspect that the retainer is actually crooked in the frame and the bolt's crookedness is a result of this).

Any suggestions for how I would get the bolt and retainer out, since they are already in the frame? Maybe my skill level just isn't up there, but they were not easy to get in at all. My truck has a 42 gallon gas tank that takes up the entire inner surfaces of the frame rails in the rear. There are a few tiny spots on the top of the rail that I had to put the bolt in and lower it into position with the piece of wire. The hitch instructions recommended fishing the bolts and retainers through with wire:

http://www.etrailer.com/instructions.aspx?pn=41511

There is a small hole on the side of the rail, but it's not big enough for anything other than a peep hole and slight redirections of the bolt with a dental pick. I had assumed this would be the same situation for all other GM half-ton trucks; maybe the large tank makes it unique?

Thanks again for your help. If I could understand how to get the bolt and retainer back out without losing them forever inside the frame rail, I'd try to flush out the inside and hopefully remove the debris that is preventing the retainer from laying flat. Let me know what you think.

old dog

it sounds like the washer is not laying flat,like the square hole in the washer and the carriage bolt are not engaged ,or the washer is cocked side ways on a corner of the block against the frame , try jiggling the bolt and block around if you can .or if you cant and can get the nut and washer on run it down a little at a time and it might straighten out .

mtp9302

I think that is exactly what's happening; the washer (I was calling it a retainer, sorry) is not laying flat inside the frame rail. My guess is that there is either a piece of debris inside the frame rail where the washer is supposed to sit, or there is some feature on the inside of the frame (weld bead?) preventing the washer from laying flat.

I tried jiggling both washer and bolt, and cranking down on them with the nut on the other side. I will try both again today, but so far these haven't worked. If I could get them back out, I would try to flush the rail out with compressed air or carb cleaner or something like that. Nothing I've done so far has worked, which is why I was wondering about slotting out the hole to allow it to fit as-is. Any thoughts on either how to get the washer to lay flat or whether it's OK to slot out the hitch hole?

old dog

if it appears that the bolt hole center line is on a seam were the frame is welded together ,there may be a weld bead tipping it a little bit .it would not be a big issue to slot the hole in the hitch some me had to do that some times ,mainly when the hitch was bent a little bit during shipping .but most time's you could tweak the hitch side plate's when they were bent in .

mtp9302

Thanks for sharing your experience. There is not a weld on the outside of the frame rail on the bolt hole. I can't see inside the frame where the washer sits, so I'm only guessing that there is something proud (debris, weld bead, burr from drilling, etc.) that is keeping the washer cocked. I know that the bolt is engaging the square hole in the washer because I can turn the nut down all the way to the frame and it tightens up.

I guess my plan is to first continue to work the bolt/washer and try to get them to sit flat (jiggling, cranking the nut down, etc.). I doubt I'll find a way to remove them from the frame; even if I did, I'm not sure that I could make the area flat because I can't see what the obstruction is that I'm up against. If this playing around continues with no improvement, I'll likely slot the hole in the hitch and put it up with the bolt as-is.

My main concern with this plan was that I wouldn't get as much clamp load on the frame/hitch with a crooked bolt. The instructions do say to tighten the nuts down to 107 ft-lbs, so maybe the effect of the crooked bolt is negligible? My guess is that there is enough meat in the hitch body so that the strength reduction due to the slot is negligible. Do you agree? I do most of the work on my cars, but this is the first hitch I've put on. I'm not sure if I'm doing something wrong or I just got a gem my first time around; either way, I appreciate the advice.

old dog

i think you will be just fine !

mtp9302

After I cranked down on the nut again, the bolt seemed to straighten out slightly but not enough. I slotted the hole in the hitch slightly (less than 1/4") to make up the rest of the difference, and it seemed to go up just fine. I didn't remove all that much material from the hitch, and the bolt seems to be clamping pretty well so I think it should be fine (just like you said). I haven't even started the wiring process, but I'm sure I will be back when I get in trouble there too...

Thanks for your help and for sharing your experience, I appreciate it.

old dog

that's good when you get to doing the wiring their is a lot of good plug in stuff avalible from drawtite that work's good http://www.draw-tite.com/