New Curt Trailer Hitch Installed on IS350
08-31-09, 06:47 AM
#16
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U.S. hitch manufactures tend to use the muffler bolts on Lexus sedans as attachment bolts -- not as highly engineered as the hitches Lexus dealers sell in Europe but easier to install.
You didn't have to wait on Curt to make a hitch for the IS. Others have had hitches fabricated for their gen 2 IS cars it's doubtful it could have been done for only $133.
I just now looked at the instructions that European Lexus dealers use to route the power wire from the rear of the IS to the battery in the engine compartment -- surprised that they route it though the car interior and under the passenger side door sills. Again, the trailer wiring harnesses Lexus sells for the IS in Europe are engineered specifically for the IS and highly engineered. Sorry, I can't post the instructions -- the PDF is way to big for this forum. If you want to see them and lots of other fun stuff, they can be viewed in the "Accessory Installation Manuals" section at http://www.lexus-tech.eu There is no need to register to see the accessory manuals.
You didn't have to wait on Curt to make a hitch for the IS. Others have had hitches fabricated for their gen 2 IS cars it's doubtful it could have been done for only $133.
I just now looked at the instructions that European Lexus dealers use to route the power wire from the rear of the IS to the battery in the engine compartment -- surprised that they route it though the car interior and under the passenger side door sills. Again, the trailer wiring harnesses Lexus sells for the IS in Europe are engineered specifically for the IS and highly engineered. Sorry, I can't post the instructions -- the PDF is way to big for this forum. If you want to see them and lots of other fun stuff, they can be viewed in the "Accessory Installation Manuals" section at http://www.lexus-tech.eu There is no need to register to see the accessory manuals.
08-31-09, 09:41 AM
#17
The existence of a trailer hitch receiver doesn't mean that the car is used for towing. Hitch receivers have many other purposes, like bike racks and tire tails. On top of that, pulling a trailer doesn't put any more stress on the drivetrain that just driving a bit faster. If a dealer tried to deny warranty on my drivetrain just because a receiver was installed, I'd take them to the mat!
08-31-09, 09:52 AM
#19
I found the hitch, and I must say I'm really disappointed in the design. Even if the 6 bolts are big and strong, the fact that they are all so close to the same rotational axis really scares me. The lever effect would mean that 200 lbs of tongue weight could easily result in 1000+ lbs on the 2 rear bolts. If you add in the load of accellerating or stopping, the load on those bolts would be much, much higher than that.
I think they should add some triangulation from the lower bar to the trunk pan to reduce the lever effect.
I think they should add some triangulation from the lower bar to the trunk pan to reduce the lever effect.
08-31-09, 10:07 AM
#21
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They also recommend a 9k mile (15,000 km) OCI. Europe is definitely different.
08-31-09, 11:32 AM
#22
08-31-09, 12:32 PM
#23
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I found the hitch, and I must say I'm really disappointed in the design. Even if the 6 bolts are big and strong, the fact that they are all so close to the same rotational axis really scares me. The lever effect would mean that 200 lbs of tongue weight could easily result in 1000+ lbs on the 2 rear bolts. If you add in the load of accellerating or stopping, the load on those bolts would be much, much higher than that.
I think they should add some triangulation from the lower bar to the trunk pan to reduce the lever effect.
I think they should add some triangulation from the lower bar to the trunk pan to reduce the lever effect.
For what it is, the Curt hitch should work just fine on an IS to tow a lightweight trailer. Hitch manufacturers don't just throw their hitches out in the market place and hope for the best. They are just as concerned with product liability as any company. There is no need to worry if the hitch is installed correctly and its capacity is not exceeded.
I've used trailer hitches on most cars I've owned since the 1960's. If I could tow a 2,600 pound sailboat/trailer combination with a 65 hp., 3,000 lb. Mercedes mid-size 240D diesel sedan, then a 3,400+ lb., 204 or 306 hp ISx50 should do screaming well towing a small trailer.
08-31-09, 02:32 PM
#25
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I think you misunderstand what we are doing. Our hitch is for a bicycle rack that carries two bikes weighing less than 20 pounds each. We are not carrying a motorcycle that together with the carrier weighs more than the allowed 200 pounds of tongue weight.
08-31-09, 03:19 PM
#27
I understand what you guys are doing. I'm just bothered that it wasn't engineered slightly better to allow other types of uses. I had a Type I hitch on my S2000 that worked well enough to tow my 3,000 + lbs boat. However, it had some triangulation with the trunk pan to eliminate the lever effect on the primary bolts behind the bumper cover.
I realize that my motorcycle and hauler would be pushing the limit on paper, but a static 260 lbs bike (including carrier) would not be an issue at all if there was triangulation. The reason I say that is because the 200 lbs tongue weight rating is assuming that the peak loads will be many times that when there's a 2000 lbs trailer attached going over bumps.
I realize that my motorcycle and hauler would be pushing the limit on paper, but a static 260 lbs bike (including carrier) would not be an issue at all if there was triangulation. The reason I say that is because the 200 lbs tongue weight rating is assuming that the peak loads will be many times that when there's a 2000 lbs trailer attached going over bumps.
08-31-09, 03:50 PM
#28
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I understand what you guys are doing. I'm just bothered that it wasn't engineered slightly better to allow other types of uses. I had a Type I hitch on my S2000 that worked well enough to tow my 3,000 + lbs boat. However, it had some triangulation with the trunk pan to eliminate the lever effect on the primary bolts behind the bumper cover.
I realize that my motorcycle and hauler would be pushing the limit on paper, but a static 260 lbs bike (including carrier) would not be an issue at all if there was triangulation. The reason I say that is because the 200 lbs tongue weight rating is assuming that the peak loads will be many times that when there's a 2000 lbs trailer attached going over bumps.
I realize that my motorcycle and hauler would be pushing the limit on paper, but a static 260 lbs bike (including carrier) would not be an issue at all if there was triangulation. The reason I say that is because the 200 lbs tongue weight rating is assuming that the peak loads will be many times that when there's a 2000 lbs trailer attached going over bumps.
I don't disagree with what you say, but I think the Curt Hitch will work well if you keep the loads light.
08-31-09, 05:54 PM
#29
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