Popping/Twisting coming from rear/middle

Hi guys,

as title suggests I have a popping/twisting sound coming from my rear end and the middle of the truck. It’s an 08 TRD sport that is stock besides 265/70/17 tires and methods.

I have an Ironman FCP 3” kit ready to go on with a diff drop. I’m wondering if it will solve this problem I’m hearing. My thoughts is it’s the factory rear leaf pack as it’s entirely straight and starting to curve downwards… the opposite of what a leaf pack is suppose to look like. Maybe it’s the u-bolts. Sound started happening after the cold winter subsided and the warmer weather has come back.

I crawled under the truck and pulled and tugged on everything I thought it could be and everything seems tight. Sometimes the truck doesn’t make the sounds. But if I go over bumps I slam the rear bump stops and the sound starts to come back. I’m wondering if I should add bump stops to the suspension upgrade and wait a little longer to install the kit. I will try to capture a video of the sound. But here’s a pic of my passenger side leafs. On a side note, how’s the rust looking down there? I get it sprayed every year. Wondering if I should get it sprayed this spring as well to help maintain it. Was gonna wire brush the axles and everything and spray some rustoleum black spray paint on them too.

 

What is it being sprayed with?

 

I take it to krown rustproofing every fall. So their fluid/rustproofing film.

 

First off, in that photo it looks like your leaf springs are 2+1 packs which are the old version. There is a TSB (or recall? I don’t know for sure which it is) to replace them with an updated 3+1 pack. Search more about that, you might get a free leaf spring replacement.

Second, you didn’t mention anything about the driveshaft/u joints/carrier bearing. I’d check those if you hear sounds coming from the center of the truck. So your U joints have zerk fittings? Do you grease them regularly? Carrier bearing have play in it?

Third, doesn’t look like your rust treatment is doing much. Switch to Woolwax and thank me later.

 

Seems logical to do that upgrade you have lined up… if it happens to solve it then two birds one stone. Otherwise you’ve at least crossed one thing off the list of potential causes…?

 

I’ll look for more info on that 3+1 leaf pack. Even if I can get them and sell them off would be good. I got the 0-440lb Ironman pack with my kit.

I will double check those areas, I’m still new to getting underneath the truck and learning about all the parts. I have a carrier bearing drop kit included with the kit, may be worth it to replace the actual carrier bearing at the same time. Drive shaft looks fine to me, but the sound does sound like a twisting then popping sometimes, so it could be a potential issue, especially with a lift where the driveshaft gets a little strained from a new awkward angle.

I don’t grease the u joints as I don’t think they have any zerks on them. But I will double check! Thanks for the info. I appreciate it. I’ll also check out wool wax, iv read some guys here swear by it. The picture isn’t the best to give you an idea of the whole frame. I’ve had buddies say it’s in great condition for an 08. But it definitely looks more rusty under there this spring then last. I wonder if the techs at krown didn’t do a great job.

 

yeah I hear that! I’ll most likely chase this sound after the install if it still exists. Due to time and money constraints. I try to do one big upgrade once a year or two.

 

I tried to give mine away for free and they're still sitting in storage. They're pretty much scrap metal so I wouldn't work that into your budget.

 

might as well forget that then haha

 

Just wanted to update and bump this thread. The source of the popping and twisting was a broken leaf spring sliding back and fourth on driver side.

iron man 4x4 FCP’s are in. I regained my factory height and more then the advertised lift height. The kit gave me a 4.5” lift front and 4 1/4” in rear. Thats with their medium coils and 0-440 leaf pack. It rides much better and feels like a tank. Besides my CV axles that left the chat instantly when we were installing everything. The boots separated just trying to get them off. Installed ecgs bushing. Gonna bring it to a shop and have them do the extended cv axles, I have no more time on my hands for working on the truck unfortunately!