curt trailer hitch install on 04 gx470
02-18-12, 03:52 PM
#1
curt trailer hitch install on 04 gx470
I spent a few hours today installing a Curt model 13445 trailer hitch on my 2004 GX470. I wanted to share a few notes from my install.
For starters, I would only suggest the Curt product if you can find one at a good price. I found this item new at an on-line thrift store and got it for under $100 including shipping. I make this suggestion because there are 2 different designs for after-market hitches for these vehicles. The one from Curt uses an 8 hole mount, 4 larger M12 bolts which utilize the tow hook holes and 4 smaller M8 bolts which utilize smaller holes behind these. The Hidden hitch product uses the an 8 bolt mount and utilizes the 4 M8 bolts in the tow hook holes, however, it only uses 2 M12 bolt and includes provisions to utilize an additional 2 M8 bolts in front of the tow hooks. GIven this design comparison, the Hidden Hitch design is clearly superior, however at $188-$200 new it is more expensive then the Curt.
CURT V HIDDEN HITCH
Quick notes on my installation.
- In order to install this product I had to disconnect the exhaust rubber isolator, remove the factory tow hook and trim the plastic cover which obstructed the 4th M8 bolt on the driver side frame rail. I did not have to relocate the factory wiring harness, instead I just mounted the plug upside down, which provide sufficient clearance for connections and keeps the plug hidden. I also suggest spraying all 8 mounting bolt locations with rust penetration spray as well as giving them a good wire brushing. Most of the welded nuts were rusty and didn't thread properly until cleaned up. I was able to install this product by myself and without a lift. I used 2 floor jacks to support the hitch as close to the frame rail as possible. I also used an electric torque wrench to make the bolting easier. I left the suspension in N position.
- After preparing all items and cleaning up the frame rail holes, get the hitch lined up using the jack stands. I started on the passenger side, with the rear most M12 bolt. Thread the bolt in about 3/4 of the way, but do not snug it down yet. Continue with the second M12 bolt. The third bolt, a M8 requires you to push the exhaust aside and the fourth M8 bolt requires you push it even further aside. NOTE: I could not get the fourth M8 bolt to thread.
- With 3 of 4 bolts 3/4 of the way in on the passenger side, start the driver side. Again the two M12 bolts are no problem, nor is the third M8. The fourth M8 bolt is obstructed by a plastic cover which I had to trim back. Even with this modification, I still could not get the fourth M8 bolt to thread on the driver side, just like the passenger side.
- With 6 of the 8 bolts now in, torque them down VERY CAREFULLY. The M12 bolts get torqued to 65 ft-lbs. The manual says to torque the M8 to 17 ft lbs, but I snapped a M8 bolt before getting to 17 (had to remove hitch and start over). I dialed the torque on the M8 bolts back to 15 ft lbs and this seems to be a safer torque value given the quality of the provided hardware.
- With everything torqued down, the last step is to make the wiring connector accessible. There are a few different solutions for this, however I decided to simply keep the plug where it is, and just turn it upside down so that the hitch does not obstruct access. The hinged door know opens downward, but it work fine in this manner. I use a 12" pigtail lead when making connections to my trailers anyway. Don't forget to re-attach the exhaust rubber isolator. This is also a good time to inspect it for wear and damage and replace as necessary.
In conclusion, not being able to get that 4th M8 bolt in on each side bothers me, but at 15-17 ft lbs these bolts don't really provide much functional value. Ultimately, this also lends evidence towards the Hidden Hitch design as being superior, as they do not use the 4th M8 bolt hole. For my need the product is fine and I will probably have a local shop weld the tail end of the hitch frame to the frame rail as opposed to the 4th bolt. I will try to post some pictures later.
For starters, I would only suggest the Curt product if you can find one at a good price. I found this item new at an on-line thrift store and got it for under $100 including shipping. I make this suggestion because there are 2 different designs for after-market hitches for these vehicles. The one from Curt uses an 8 hole mount, 4 larger M12 bolts which utilize the tow hook holes and 4 smaller M8 bolts which utilize smaller holes behind these. The Hidden hitch product uses the an 8 bolt mount and utilizes the 4 M8 bolts in the tow hook holes, however, it only uses 2 M12 bolt and includes provisions to utilize an additional 2 M8 bolts in front of the tow hooks. GIven this design comparison, the Hidden Hitch design is clearly superior, however at $188-$200 new it is more expensive then the Curt.
CURT V HIDDEN HITCH
Quick notes on my installation.
- In order to install this product I had to disconnect the exhaust rubber isolator, remove the factory tow hook and trim the plastic cover which obstructed the 4th M8 bolt on the driver side frame rail. I did not have to relocate the factory wiring harness, instead I just mounted the plug upside down, which provide sufficient clearance for connections and keeps the plug hidden. I also suggest spraying all 8 mounting bolt locations with rust penetration spray as well as giving them a good wire brushing. Most of the welded nuts were rusty and didn't thread properly until cleaned up. I was able to install this product by myself and without a lift. I used 2 floor jacks to support the hitch as close to the frame rail as possible. I also used an electric torque wrench to make the bolting easier. I left the suspension in N position.
- After preparing all items and cleaning up the frame rail holes, get the hitch lined up using the jack stands. I started on the passenger side, with the rear most M12 bolt. Thread the bolt in about 3/4 of the way, but do not snug it down yet. Continue with the second M12 bolt. The third bolt, a M8 requires you to push the exhaust aside and the fourth M8 bolt requires you push it even further aside. NOTE: I could not get the fourth M8 bolt to thread.
- With 3 of 4 bolts 3/4 of the way in on the passenger side, start the driver side. Again the two M12 bolts are no problem, nor is the third M8. The fourth M8 bolt is obstructed by a plastic cover which I had to trim back. Even with this modification, I still could not get the fourth M8 bolt to thread on the driver side, just like the passenger side.
- With 6 of the 8 bolts now in, torque them down VERY CAREFULLY. The M12 bolts get torqued to 65 ft-lbs. The manual says to torque the M8 to 17 ft lbs, but I snapped a M8 bolt before getting to 17 (had to remove hitch and start over). I dialed the torque on the M8 bolts back to 15 ft lbs and this seems to be a safer torque value given the quality of the provided hardware.
- With everything torqued down, the last step is to make the wiring connector accessible. There are a few different solutions for this, however I decided to simply keep the plug where it is, and just turn it upside down so that the hitch does not obstruct access. The hinged door know opens downward, but it work fine in this manner. I use a 12" pigtail lead when making connections to my trailers anyway. Don't forget to re-attach the exhaust rubber isolator. This is also a good time to inspect it for wear and damage and replace as necessary.
In conclusion, not being able to get that 4th M8 bolt in on each side bothers me, but at 15-17 ft lbs these bolts don't really provide much functional value. Ultimately, this also lends evidence towards the Hidden Hitch design as being superior, as they do not use the 4th M8 bolt hole. For my need the product is fine and I will probably have a local shop weld the tail end of the hitch frame to the frame rail as opposed to the 4th bolt. I will try to post some pictures later.
Last edited by z0lt3c; 04-26-12 at 04:40 PM.
02-19-12, 02:55 PM
#3
Good job. Those that can create installs with pictures, really help others and what this forum is all about. Had you checked the most recent post on "hitch for the GX", you would read that I had installed the Curt hitch. I did not do an install thread, just responded to a question from someone who started the post and wanted to know about the different models. I bought mine online for $125.00 last year, which included shipping.
My only difference in the install, is that I used a tap in the smaller holes to clean the rust out of the threaded holes. I used old towels wrapped and taped to the top of my jack stands, not to scratch the power coat paint. Jack stands work well, when you are the only person doing the install (great minds think alike).
Second, I too had the same problem with the holes not lining up. No matter which side I installed first, one hole in each side didn't line up. What I did was use a grease pencil, to mark the opening, where the hole didn't line up, so I could enlarge that side of the hole in the hitch. I used a dremel grinder to open the hole about a 1/16 on one side. I did that on both left and right side. Walla!, all bolts in. I too felt uncomfortable leaving one bolt out on each side.
Nice heavy duty hitch, I too would recomend this. If you install one side and the bolts don't line up on the other side in one hole, you can let it hand down, still supported by the loose bolts in the other side, to enlarge the opening in the hitch bracket. Safety glasses a must when grinding on the hole.
When I wax my car, I wax my hitch. ****. Even with that and one winter, paint hasn't come off, but I am not a big fan of powder coating. I am sure every brand it. Here is my picture (although dark)
My only difference in the install, is that I used a tap in the smaller holes to clean the rust out of the threaded holes. I used old towels wrapped and taped to the top of my jack stands, not to scratch the power coat paint. Jack stands work well, when you are the only person doing the install (great minds think alike).
Second, I too had the same problem with the holes not lining up. No matter which side I installed first, one hole in each side didn't line up. What I did was use a grease pencil, to mark the opening, where the hole didn't line up, so I could enlarge that side of the hole in the hitch. I used a dremel grinder to open the hole about a 1/16 on one side. I did that on both left and right side. Walla!, all bolts in. I too felt uncomfortable leaving one bolt out on each side.
Nice heavy duty hitch, I too would recomend this. If you install one side and the bolts don't line up on the other side in one hole, you can let it hand down, still supported by the loose bolts in the other side, to enlarge the opening in the hitch bracket. Safety glasses a must when grinding on the hole.
When I wax my car, I wax my hitch. ****. Even with that and one winter, paint hasn't come off, but I am not a big fan of powder coating. I am sure every brand it. Here is my picture (although dark)
Last edited by Ancient; 02-19-12 at 03:10 PM.
02-19-12, 03:45 PM
#4
Thanks for the comments.
Nice job with your install ! I see you even have the correct bumper trim piece and the rubber trailer hitch cover. Those items are still on my to-do list. The pictures (I just added) are after just 1 day on the truck, so this thing is certainly going to get dirty.
Nice job with your install ! I see you even have the correct bumper trim piece and the rubber trailer hitch cover. Those items are still on my to-do list. The pictures (I just added) are after just 1 day on the truck, so this thing is certainly going to get dirty.
04-04-12, 07:24 PM
#6
Thanks for the write-up, guys. I had the Curt hitch installed recently on my '03. One question. Where exactly is the wiring point underneath? I'm not exactly sure what I'm supposed to be looking for. I usually use the hitch for a big bike rack but I may need to go collect a swingset on a trailer this weekend. I /believe/ that all of the wiring is back there already, though I need to climb under there tomorrow to have a look.
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04-05-12, 11:03 AM
#9
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Help me understand something on the hitch please.
I just purchased a 2007 used. Mine has the circle lighting adapter under it, and looks like with four bolts you could put a 2 inch reciever hitch on there, is this not true?
Do you have the curt hitch that attaches all the way around ?
thanks.
I just purchased a 2007 used. Mine has the circle lighting adapter under it, and looks like with four bolts you could put a 2 inch reciever hitch on there, is this not true?
Do you have the curt hitch that attaches all the way around ?
thanks.
04-05-12, 11:11 AM
#10
Lexus Champion
04-06-12, 12:47 PM
#11
Lexus Champion
i just installed a OEM hitch yesterday and the smaller bolts that are the forward most facing bolts (front of the GX) are very easy to snap off by over torquing. I snapped one off on the drivers side but luckily it had enough shank I was able to use come channel lock plies to get it out. The instructions said to torque the larger bolts to 65ftlb +/- 12lbs. and the smaller bolts to 19ftlb +/- 4lbs...I suggest for the smaller bolts you go -4lbs. I dialed it down to 10lb just to be safe.
Other than that the: instructions from Sewell were spot on, however I didnt need to remove the muffler from the rubber mount, I was able to wiggle my hands to get the 2 smaller bolts in there. If you have a set of: these theyll come in really handy.
Other than that the: instructions from Sewell were spot on, however I didnt need to remove the muffler from the rubber mount, I was able to wiggle my hands to get the 2 smaller bolts in there. If you have a set of: these theyll come in really handy.
04-26-12, 04:44 PM
#13
I was able to borrow a friends lift and time to inspect the issues w/ the 4th M8 bolt not threading. He suggested retapping all 4 M8 frame mounting points, after which all points are now functional. The 2 front most points, which I could not get to thread at all, do not appear to have been threaded, or the threading was sheared off at some point. I would suggest tapping, at least, the front most two mounting points, before attempting the install.
04-27-12, 08:34 PM
#14
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I installed my curt hitch last week. Retapped all if the holes to save time. And it did. Complete install in 30 minutes. Only issue I had was the 7-pin connection. After reading the post I guess I can flip it upside down. Over all it is a great hitch. I have the two relay under the hood for lighting, but I can't find the rear relay. I thought I read somewhere it was located under the left taillight. I took light out and couldn't find it. Took the jack over off, couldn't find it. Can anyone point me in the right direction. I want to know if my truck was ow preped
04-27-12, 08:35 PM
#15
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I installed my curt hitch last week. Retapped all if the holes to save time. And it did. Complete install in 30 minutes. Only issue I had was the 7-pin connection. After reading the post I guess I can flip it upside down. Over all it is a great hitch. I have the two relay under the hood for lighting, but I can't find the rear relay. I thought I read somewhere it was located under the left taillight. I took light out and couldn't find it. Took the jack over off, couldn't find it. Can anyone point me in the right direction. I want to know if my truck was ow preped from factory. Given the 2 relay under the hood and the rear sub bracket for a factory hitch.