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Posted

I know if I had one of these trucks that was having an issue I'd figure out a way to mount a camera in different areas of the truck to see what was going on while driving.

Posted

Thanks for the info fullboost! I wound up taking mine off for the week and torquing the ubolts down to 110 ft/lbs and bumping my air pressure up to 38 and my truck is as smooth as it's ever been. I haven't had it out on the highway yet but it's definitely better around town. I think torquing them that tight is essentially like putting a spring clamp on compressing the spring a little more. I might put my clamps back on the rear and report back but am hesitant to since its riding so well lately and don't want to mess it up.

 

I am curious if anyone else has tried them in the rear though and how that effected it.

 

 

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So you took off the supplemental clamps and just tightened your U-Bolts?

 

and mine are at 30-31 psi but its also only 2 degrees currently

Posted (edited)

 

So you took off the supplemental clamps and just tightened your U-Bolts?

 

and mine are at 30-31 psi but its also only 2 degrees currently

Yeah, I have 305-55-20 Nittos on my truck and they flat spot with the slightest change in temp. I think bumping the psi for me helped reduce that, but also the spring clamps made the truck stiffer so I felt the flat spot more until it warmed up. My truck has always had the highway vibe even after 4 sets of different brand tires, and 2 sets of wheels, factory and aftermarket. The spring clamps definitely helped my truck feel less "aftershock/resonance" after hitting potholes etc. I will most certainly put them back on at some point to see if they help the highway vibe and I will try front and rear. Like I said before though it rides great around town now and am hesitant to mess with it.

 

I believe factory setting for the u-bolts is 78 ft/lbs but when I checked mine initially a few mos ago they were less than 45, barely tight from new, so I torqued them to 78 and then kept going from there. One member said he got completely rid of his highway vibe by torquing them to 130, so I figured I would try tightening them down in increments.

 

 

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Edited by hotrodz37
Posted

1) in front axle

2)Placed them about 6" in front of the axle

 

3) I didn't use a TQ wrench, just till I had them tight and the assist spring under load

 

4) Shocks - Standard/Stock Shocks

 

5) 4wd

6) Cab style and bed length- Extended Cab/ Standard Bed

 

7) empty bed

8) The springs seem to have definitely helped, truck seems soother at all MPH but it did not completely remove the vibration i had at 60-75mph. I'd say it was about a 80% reduction. 100% WORTH IT and a lot better than it was

 

9) I did not try in rear of the axle but my truck does have the Max Trailering Package so idk if i have different shocks or rear leafs in the back compared to a standard truck

Pics

Heres the clamps i used from AutoZone for 16.99

9rnEN8M.jpg

And this is where they are on the truck

Ha80rdF.jpg

Same clamps I installed. Any update on how it rides?

Looking forward to hearing your status update.

 

 

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Posted

Thanks for the info fullboost! I wound up taking mine off for the week and torquing the ubolts down to 110 ft/lbs and bumping my air pressure up to 38 and my truck is as smooth as it's ever been. I haven't had it out on the highway yet but it's definitely better around town. I think torquing them that tight is essentially like putting a spring clamp on compressing the spring a little more. I might put my clamps back on the rear and report back but am hesitant to since its riding so well lately and don't want to mess it up.

 

I am curious if anyone else has tried them in the rear though and how that effected it.

 

 

Sent from my iPhone using Tapatalk

 

I just did the same, torqued them down to 110ft/lbs but I left the clamps on; Improvement is amazing. Mine weren't even torqued down to 40ft/lbs.

 

Once it gets warmer and my truck isn't dirty as hell from the snow/ice I'll probably try removing the clamps.

Posted

All this talk about loose u bolts on a lot of yall trucks makes me want to torque mine down properly this weekend while I'm working on it

  • Like 1
Posted

I'm not 100% certain these u-bolts can handle the 110ft/lb over time. Everything that I've been looking up seems like it should either be 90ft/lb for grade 5 9/16"-18 U-bolts or ~130 for grade 8 u-bolts. (I'm guessing on the 9/16" diameter based on the 21mm nut size). If someone has the service manual for these trucks it would be nice to know what GM specifies for the torque spec; Either way less than 40ft/lbs isn't anywhere close to what they should be.

  • Like 1
Posted

 

I just did the same, torqued them down to 110ft/lbs but I left the clamps on; Improvement is amazing. Mine weren't even torqued down to 40ft/lbs.

 

Once it gets warmer and my truck isn't dirty as hell from the snow/ice I'll probably try removing the clamps.

Glad to hear. My truck has not had the 74 to 85 vibration since I tightened the hell out of my u-bolts a good while back. I added the clamps afterwards just to see what they would do and really made it ride much better, so Iam leaving them on.

  • Like 1
Posted

Does this apply to the 2500s as well?

 

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If I had to take a guess, your u-bolts are probably stronger so they are probably torque spec'd higher than the 1500s.

Posted

Glad to hear. My truck has not had the 74 to 85 vibration since I tightened the hell out of my u-bolts a good while back. I added the clamps afterwards just to see what they would do and really made it ride much better, so Iam leaving them on.

 

Where did you put the clamps at? I'm thinking about pushing mine closer to the axle first before I take them off. I have mine about 5" in front at the moment.

Posted

 

Where did you put the clamps at? I'm thinking about pushing mine closer to the axle first before I take them off. I have mine about 5" in front at the moment.

I have the clamps 4 inches in front of the blocks.

  • Like 1
Posted

Let me restate; does the process impact the 2500s the same way with some of that road hop? Has anyone done this on a 2500 and experienced positive results?

 

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