Installing a Trailboss 2" rear lift block on a non-trailboss truck

fondupot · January 22

U-joints have not showed up yet. They got delayed in the weather over the weekend. Tracking shows them out for delivery today.

Over the weekend though, I loosened everything, including shocks this time and attempted to “straighten” my axle so it was even on both sides from the spring perch to the from bolt on the leaf spring.

Unfortunately, it didn’t seem to make any difference. Still have tiny bit of vibration that’s noticeable at highway speeds. And a pretty consistent rumble/vibe when slowing down. Right around 25-20 mph.

Starting to regret the 2” blocks….

Vincej138 · January 22

5 minutes ago, fondupot said:

U-joints have not showed up yet. They got delayed in the weather over the weekend. Tracking shows them out for delivery today.

Over the weekend though, I loosened everything, including shocks this time and attempted to “straighten” my axle so it was even on both sides from the spring perch to the from bolt on the leaf spring.

Unfortunately, it didn’t seem to make any difference. Still have tiny bit of vibration that’s noticeable at highway speeds. And a pretty consistent rumble/vibe when slowing down. Right around 25-20 mph.

Starting to regret the 2” blocks….

I've always personally stayed away from blocks. You could look into a shackle perhaps. Belltech and Maxtrac should make some.

fondupot · January 23

20 hours ago, Vincej138 said:

I've always personally stayed away from blocks. You could look into a shackle perhaps. Belltech and Maxtrac should make some.

I didn’t think I would encounter anything like this using an OEM block. This is the same setup that Trailboss trucks utilize.

My new u-joints are out for delivery. DHL sucks they said they tried to deliver yesterday…but I was working from home and they never showed up.

Hopefully I can get those installed ASAP.

fondupot · January 25

Finally got my new u-joints in the mail. Unfortunately it's raining today and tomorrow, so I wont be able to work on the truck.

If the new u-joints don't resolve my problem, I am considering alternative options, like a tapered 2" block.

fondupot · January 26

Well the rain held out this morning, so I was able to get the new u-joints installed on the driveshaft today. Not a terribly difficult install, took me about 4 hours. The old ones didn't seem too bad, the seals looked like they'd seen better days, but the grease inside seemed clean. The old u-joints didn't appear to have any excess play that I could tell moving them by hand.

Anyways, new u-joints are in, they do feel much tighter all around compared to the old ones, even after seating the caps with a hammer. I could move them freely by hand and they felt smooth, so I'm not worried about any binding. Got the driveshaft reinstalled without any issue.

The 4 bolts that hold the rear yoke to the pinion plate are 15mm. I couldn't fit my torque wrench on them to tighten to the specified 74 ft/lbs, so I just ugga-dugga-ed them as best I could with a 15mm crescent wrench. I removed all the old thread locker on the bolts before reinstalling and used some blue removable thread locker on the bolts before reinstalling.

Partial Verdict:

Took the truck for a test drive after getting it put back together. I was only able to get it up to about 65mph on the country roads around me. But everything between 35-65 seemed pretty smooth. I want to say it seems to feel better. But once I get it on the highway and do some 70+mph speeds, it will be more definitive. There is still a little bit of vibration when slowing down between 25-20mph, but I think it is much less than before.

I will report back after I have a chance to do some highway driving.

Edited January 26 by fondupot

fondupot · January 30

Drove about 300 miles yesterday, all interstate driving between 70-75mph. The vibration is significantly reduced. But I still have some noise. BUT I don't think its coming from the u-joints or driveshaft anymore.

I noticed my two rear tires have some considerable feathering on the inside edge, and actually worn quite smooth. You can run your hand along the inside edge of the tires and feel the feathering.

These tires were rotated front to back around the same time I installed the 2" lift blocks. AND I think they were not rotated for ~12,000 miles before that. I usually have them rotated at each oil change, but one time I think my shop forgot to rotate them. I knew my front struts at the time were starting to go bad, and I might have some alignment issues, and finally got around to having new struts installed. So I think the extended period of non-rotation and misalignment on the original struts caused some feathering. And now that they are rotated to the back, they are starting to run "flat" again and its causing some tire noise.

Timeline of events:

9/29/2023 - Oil change & Tire rotation - 82,347 miles

11/3/2023 - Oil change and MISSED tire rotation - 88,498 miles

12/15/2023 - Oil change and Tire Rotation - 94,946 miles

12/16/2023 - Rear 2" Block Installed, and new rear shocks - 94,959 miles (started to notice the noise/vibe at this time)

1/4/2024 - New Front Struts & Alignment - 95,117 miles

So between my September service and December service, I think the tires did not get rotated (I had a suspicion back then because one tire had higher PSI and I checked them before and after the service and it stayed in the same spot). That accounts for roughly 12,599 miles. And I also suspected my OEM original struts up front were worn and the alignment was starting to go bad. So that 12,599 miles feathered those front tires. Then in December I witnessed the tires actually get rotated front to back. Blocks got installed and then I started noticing the noise....

So I probably didn't need to install new u-joints. But I guess it didn't hurt.

It's all starting to add up now.

Edited January 30 by fondupot

AJMBLAZER · January 30

Good detective work.

fondupot · January 31

23 hours ago, AJMBLAZER said:

Good detective work.

Thanks. Did another 300 miles today. It’s super annoying at 70-75 mph. It does seem to go away when coasting, that’s interesting.

Idk, how long it will take for the feathering to even out, it’s been about 1600 miles since rotating them and having it aligned. These tires only have about 30k on them. I would hate to have to replace them…

fondupot · February 17

Just a small update. I decided to remove the 2” Trailboss blocks and installed a 1.25” block that comes off a Colorado ZR2. They fit the full size trucks too. I put all new u- bolts and nuts on as well. Part numbers listed below for anyone interested. The truck sits a little better now I think. Less nose dived look.

ZR2 Colorado blocks - 15885530

u-bolts - 11569811

Nuts - 11549170

I also rotated my rear tires (the feathered ones) side to side to ease some of the feathering tire noise. Seemed to quiet them then some. It’s the inner edge of my rear tires that feel like a saw blade in one direction. So when I flipped them, I put the “sharp” edges facing back.

Haven’t taken the truck on the highway yet, but it does feel better. Hopefully the tires will just even out eventually.

Whatever I did today, I no longer have the vibration when slowing down between 25-20mph. Not sure what helped that…but glad it’s gone. So that’s good.