Extreme drop center crossmember troubles!!

[project76]

After installing the crossmember my truck is now 3" higher in the rear. Due to moving the trailing arm mounting points up on the crossmember to correct pinion angle, my trailing arms now hit way sooner. I already have 2" blocks so i know im gonna have to hack on my truck some more. Would it be safer to hack on the frame, the trailing arms or both? Would i benifit from the tubular trailing arms out there? Im even considering scrapping the whole idea and doing a 4 link. Does anyone have any other ideas before i burn this thing?

[XXL]

Originally Posted by project76

After installing the crossmember my truck is now 3" higher in the rear. Due to moving the trailing arm mounting points up on the crossmember to correct pinion angle, my trailing arms now hit way sooner.

Cut the frame and leave the trailing arms alone. You can get the kind of reinforcement you need back into the frame, but you'd be mucking with the structural integrity of the trailing arms in a way that I don't think you could overcome easily.

[gringoloco]

-Unbolt and flip-over the trailing arm mounts, putting them back in the stock position. Cut off and reuse or get the weld-on perches to correct pinion angle.

-The tubulars may give you some clearance, but not three inches. You would still have to notch the frame to clear them.

Maybe combine these two- i.e. flip the brackets/weld on perches, and notch frame/tubular arms. Might not have to notch for the arms in this case.

Sucks but that's about it without going four-link. Let us know how it goes.

-Chris

[fastbagged68]

A couple different things you could do.
1. You can cut the perchs off of your rearend and move them in about an 1inch. There is enough movement in the front bushings to do this.
2. Use the factory mounts on the crossmember, and move the crossmember to center wheel in wheelwell. When you lay these trucks out the wheel gets tucked into the front of the wheel well.
3. Go with tubular arms. The ones from CCP will gain some clearance.
4. Go with a 3 inch block. I usually run a 3" block if I am laying it out.
5. Or go with a 4 link and solve all problems. I wish I did a 4 link @ times. Would have saved me alot of time and a smaller notch.
My next truck is going with a 4 link!!!!

[XXL]

Originally Posted by project76

Does anyone have any other ideas before i burn this thing?

You know... you could make me a smokin' deal on the crossmember, and give me a few days to swap it out and send you back my stock unit

[see ten]

I don't have any interference problems with mine, but it was a mutha to get it in.

[XXL]

Originally Posted by see ten

I don't have any interference problems with mine, but it was a mutha to get it in.

Problem on OP's truck is that he's VERY low, and so the interference is with the trailing arm hitting the frame itself. And this is exascerbated by the raised pivot point of the new xmember.

[project76]

for some reason my trailing arm mounts are welded to the crossmember. When i ordered the crossmember they were bolted in the picture, but mine were welded when i got it here. I tried to contact CPP but i havent received a responce yet. Here is a few shots of my issue.

[67Fleet]

hmm, in that last pic it looks like if you route the exhaust through the crossmember you might still have some issues clearing that also.

[project76]

Yeah thats another issue im gonna have to deal with. I finally had a chance to talk with CPP but now i have to call and talk with someone else in the morning. Hopefully i am able to exchange mine for the style that i paid for.

[XXL]

Originally Posted by project76

Hopefully i am able to exchange mine for the style that i paid for.

Keep us posted. Bolted is what I'd be after as well. When you lower these things a long way, the rear wheel centerline gets pulled forward so it's no longer centered in the wheel opening. With the bolt-on hangars, you can space them out to move the wheel centerline back where it belongs.

[SCOTI]

Originally Posted by XXL

Keep us posted. Bolted is what I'd be after as well. When you lower these things a long way, the rear wheel centerline gets pulled forward so it's no longer centered in the wheel opening. With the bolt-on hangars, you can space them out to move the wheel centerline back where it belongs.

You could bolt the entire c-member in a little further back too (but that won't help the OP's issue).

[project76]

After talking with Tech support at CPP i guess im SOL. They do not make the bolt on perch cross members anymore. That was a first run only. I have no idea why they have it pictured this way on the web site. If i had known this, i would have went elsewhere. So i can either send it back and pay for shipping and a restocking fee or try some mods brought up by you guys. Im alittle mad so im gonna take a break for a few days and calm down. Maybe ill end up with a 4 link after all

[XXL]

Originally Posted by project76

After talking with Tech support at CPP i guess im SOL. They do not make the bolt on perch cross members anymore. That was a first run only. I have no idea why they have it pictured this way on the web site. If i had known this, i would have went elsewhere. So i can either send it back and pay for shipping and a restocking fee or try some mods brought up by you guys. Im alittle mad so im gonna take a break for a few days and calm down. Maybe ill end up with a 4 link after all

Did you pay with cc? If yes, get them involved. Tell them the product is not as advertised and your efforts to get resolution have been unsuccessful. Then CPP can suck eggs. Oh, and I've captured a PDF of the web site in case you need it to show what you thought you were buying (on the off chance they change the pic).

[project76]

Originally Posted by XXL

Did you pay with cc? If yes, get them involved. Tell them the product is not as advertised and your efforts to get resolution have been unsuccessful. Then CPP can suck eggs. Oh, and I've captured a PDF of the web site in case you need it to show what you thought you were buying (on the off chance they change the pic).

I did pay with a credit card, thanks for bringing that up. I will call the bank and see where i can go from here. You have been a huge help and i cant thank you enough.

[gringoloco]

I think ECE's is still bolt together. I'd be sure and ask first though...

-Chris

[see ten]

Originally Posted by gringoloco

I think ECE's is still bolt together. I'd be sure and ask first though...

-Chris

Yep, mine is bolted together.

[copper71]

That's because CPP used a pic of Early Classic's Crossmember. I purchased mine from ECE. It works great. ECE developed the part and obviously did the research!

[70 CST 4X4]

I helped my buddy put one we picked up from Early Classic in his 69(his truck is pretty low) and we had no problems. Nice fit and they were great guys to deal with. They were quick to answer all the questions we had. Their mounts are bolted in and we had no clearance issues.

70 CST 4X4

[shifty]

Got some related no-brainer questions here:

When dropping greater than 5/7 using the stock trailing arms, regardless of whether you're using either ECE or CPP crossmember, your pinion angle is going to be shot, and you're going to need to cut off and re-weld the perches, right? I was under the impression that the lifted angle of the trailing arm mounts for the "extreme drop" crossmembers actually corrected the pinion angle to some degree.

Also, a question for see ten - you know, I see under your extreme drop crossmember you have a support bracket under the framerail beneath the bottom two bolts. Did that come with your crossmember? I saw on the CPP unit install in CCT mag that they installed one on theirs in the same location. I'm just curious about whether it's required, and what the purpose is.

[gringoloco]

Originally Posted by shifty

I was under the impression that the lifted angle of the trailing arm mounts for the "extreme drop" crossmembers actually corrected the pinion angle to some degree.

Yes, but not without sacrificing clearance between the trailing arms and frame where they pass under. That is what caused project76 so much trouble.

Originally Posted by shifty

Also, a question for see ten - you know, I see under your extreme drop crossmember you have a support bracket under the framerail beneath the bottom two bolts. Did that come with your crossmember? I saw on the CPP unit install in CCT mag that they installed one on theirs in the same location. I'm just curious about whether it's required, and what the purpose is.

That is a stock reinforcement plate. Your frame may have them in place from the factory. I have seen them both ways...

[SCOTI]

When dropping greater than 5/7 using the stock trailing arms, regardless of whether you're using either ECE or CPP crossmember, your pinion angle is going to be shot,

Define "shot"?

My 68 was @ least a 7" drop in the back w/bags + blocks. I used the stock OE trailing arms & crossmember. This set-up used 1-set of u-joints that were swapped in when the suspension was done @ the time of purchase (they're still in service).

No vibrations or issues otherwise in 5+ years of service.

[shifty]

"shot" - "out of whack" - "in need of correction"

e.g., if i want to do this properly with no smacking the frame, no other issues, i'm going to be measuring for proper pinion angles, removing stock perches from my axle and welding them back on in a different place.

[SCOTI]

Originally Posted by shifty

e.g., if i want to do this properly with no smacking the frame, no other issues, i'm going to be measuring for proper pinion angles, removing stock perches from my axle and welding them back on in a different place.

Like I posted, no problems @ all on mine (definitely no issues w/the trailing arms hitting the frame).

No need to cut the perches off either. They make pinion wedges for adjusting pinion angle on trailing arm suspensions.

[shifty]

Shoulda remembered that, I had to install 2º pinion shims on m '03 Sierra when I dropped it.



Cool, so I'll leave the perches in place and look at the geometry before getting gung-ho and hacking anything off first.