hit a really big road repair this morning and then "clunck!"

[v7guy]

Mark, we'll see how fast I can work. If I can't manage to build a rear bumper in a reasonable amount of time I'll give you a holler.




Update on how I'm going to proceed...
Looked for a belleville washer for awhile but decided it would be taking up shock travel that I don't have and I'm not so sure that it's really a solution. Many on here cautioning that I may need to have a steel bumper to weigh the truck down enough to have a little shock travel obviously raised valid concerns. So today I grabbed a Badlands 12k winch. I've read enough about it that I'm fairly confident it's a decent (but real slow) winch. It should meet my needs for occasional wheeling. The combo of winch and bumper should alleviate topping the shock out to a large degree. I guess time will tell.

[v7guy]

Got it all back together and took it for a long drive, no noticeable bending of the washer yet. You can see how compressed the spring is and how compressed the bushing is in the pics above.

I'm going to try to bang out the body lift tomorrow and I'll start on the front bumper this weekend. If Mike can build one in a day maybe i can do it in two or three.

[DannoWS6]

Good info here, sorry about the bad luck v7guy.

I know this thread is a bit old, but I'm reading it and I think I can relate to some degree with what the OP is experiencing and wondering if anybody could confirm my assumptions?
So I have a RC lift and Bilstein HD's. Ever since installed I noticed whenever I got over an uneven road or a bump quickly (especially an even drop, where the front tires leave the ground for a split second) that the suspension on extension BANGS REALLY loud. Like a hammer to the floorboards. I thought the Bilsteins had a built in bumpstop? Anyways , this does not happen often, I drive like grandma, but when it does its loud as hell.

So what you guys are saying is that when the extension max's out and slams, thats expected with a lift like BDS or RC? I always wondered what the heck is going on and had me concerned. Its a 2008 Envoy SLE, I have no idea what the front spring #'s are, but man when it does that it wakes you up. Wish there was something I could do to prevent it?

[Trail X]

About the only prevention is adding washers below your top shock mount to increase the effective extension length.

[DirtyBacon04]

@JD: That statement confuses me. How will lowering the strut as an assy (giving OTS lift) prevent topping out? The mechanics of it aren't playing out in my noggin...

[Trail X]

This should clear things up some:

[chevycrew]

Basically the washers make the strut assembly longer, giving a little more travel before "topping out"

[v7guy]

If we're talking about Marks 3" lift. Just putting washers below the lower bushing washer at the top mount would just let the shock extend to the maximum unless you have enough weight on the front to weigh down the front end.
A longer spacer through the rubber bushing might help when we top out since the upper rubber piece wouldn't be compressed so much, so it should be able to act as a super crappy bump stop. But i think we're at the point where this is the limit. I don't know that washers and 89 springs are a good idea.

From here on our options are the coilovers, which is the best solution to lifting the front. Or building a subframe to drop the diff, or of course an SAS.

I toyed with the idea of dropping the front diff but I'm not so sure it's worth the trouble at this point. If we break parts with our current lifts and 34s then being able to put bigger tires on is just going to break parts more quickly. At this point a Dana 60 seems like the most cost effective option if you're going to go bigger.

[Trail X]

But i think we're at the point where this is the limit.

From here on our options are the coilovers, which is the best solution to lifting the front. Or building a subframe to drop the diff, or of course an SAS.

A good observation. I would not feel safe putting more lift on the front of mine, from a reliability standpoint. I could probably raise it another inch, but it would top out all the time, which will eventually destroy something.

One option that you didn't mention is a high angle CV shaft. I believe these are actually fairly "common" on Tahoes, because their CV shaft is like 6" long:


Maybe something we can adopt as we move forward. At least, that's our limiting element right now with flipped UCAs.

[DirtyBacon04]

This should clear things up some:

OH ok!
I was thinking of the wrong spot for the washers. Now I get it.

[fishsticks]

From here on our options are the coilovers, which is the best solution to lifting the front. Or building a subframe to drop the diff, or of course an SAS.

I toyed with the idea of dropping the front diff but I'm not so sure it's worth the trouble at this point. If we break parts with our current lifts and 34s then being able to put bigger tires on is just going to break parts more quickly. At this point a Dana 60 seems like the most cost effective option if you're going to go bigger.

I looked closely at dropping the front subframe/diff... To the point of having drawn up plans for brackets etc. The amount of drop required to clear the oil pan without raising the motor is something like 7 inches or so. You end up LOSING ground clearance unless you increase the tire size. 35s are about the limit of what the outer CVs will put up with, assuming a locker.

This is before you get into the steering geometry problems...

[v7guy]

I didn't mention the high angle CV joints because the last time i checked they were in the neighborhood of a couple grand (those RCV custom axles are expensive) . Then you're still stuck with the 26 spline inners... then you start thinking... well if I'm dropping the diff why not use a bigger front diff with a higher spline count... then you realize you're stuck with the 27 spline outer, and changing that means changing the whole upright. Which is great because then you can use a real wheel bearing, but then your loosing ABS and changing the A arms... Then you realize, hell, might as well make it long arm and stuff some 39s on it. Then, as mentioned, you still have to play with the steering. I looked into it to, I even have a second front diff here so I could mock it up in a frame. I came to the same conclusion as Donny.

Then after all that you've spent a ton of money and time and your shit is still gonna break before a Dana 60 on leafs or a 3 link. At that point you just start looking for a Dana 60... if you want to go bigger.

[Trail X]

You're making it sound quite complicated. The idea behind going with a high angle CV shaft is to NOT have to relocate the diff. From my understanding, it would have a CV outer, and replace the tripod with a CV inner. Then the shaft takes the addition of a extension joint.

Personally, I think it would allow me to get a few more inches of down travel and fit 35s without a body lift. But it's all a pipe dream anyways. It's not something I'm willing to spend money on right now. Plus, to fit 35s I'd need to regear. So if anyone wants to donate a couple grand I'll be all over it.

[The Roadie]

..then you realize you're stuck with the 27 spline outer, ...

I also fantasized about this LONG ago, and considered swapping to Tahoe CV outers (spliced to the GMT360 inners) and machining the steering knuckles to accept their hubs. Also solves the need for adapters, since the Tahoe hubs would come with the proper size bolt pattern. Heck, for all I know the Tahoe hubs use the same mounting holes as ours.

[v7guy]

You're making it sound quite complicated. The idea behind going with a high angle CV shaft is to NOT have to relocate the diff. From my understanding, it would have a CV outer, and replace the tripod with a CV inner. Then the shaft takes the addition of a extension joint.

Personally, I think it would allow me to get a few more inches of down travel and fit 35s without a body lift. But it's all a pipe dream anyways. It's not something I'm willing to spend money on right now. Plus, to fit 35s I'd need to regear. So if anyone wants to donate a couple grand I'll be all over it.

That's my understanding as well, 2 CVs. If we got another couple inches of down travel wouldn't the back side of the upright be hitting the spring? I can just barely fit my fingers between the two when i'm at full droop.
Wouldn't we also need the coilovers to use the extra couple inches of down travel?
Would we be maxing out the balljoints with another couple inches, even with the flipped uppers?

I've given this a considerable amount of thought and I have more time than I know what to do with for the next few months. So I've been laying around thinking "what if" lately and debating the pros and cons. Cause you know, what else is there to do?

:edit:

Bill, wouldn't that be nice if the tahoe used the same bolt pattern, ABS ring and had the same diameter, all you had to do is bolt them into the upright? I don't suppose you know if they have the same spline count on the axles do you? I suppose all someone would have to do is go to the parts store and measure one.
Could probably get one made with one number of splines to match each side for a lot cheaper than the whole CV axle.
My previous concerns still stand though

[Trail X]

Its easy to make new drive shafts per your specifications from a parts bin, not so easy to do the same thing with knuckles and hubs

True that it may get a bit tight for the stock springs to go down much more. I hadn't thought of that. Though I seem to have more space on mine than I've seen on most - for some reason or other.

I don't think we'd run into ball joint issues with a couple more inches. Ideally, you'd add 2 or 3 inches of droop, but only add maybe 1" to the ride height (in my opinion).

Wouldn't have to do coilovers, but might have to cobble up your own top spacer. I could see something like a .7" top spacer combined with a "shock elongator". That might be just about right on mine for 35s.

[fishsticks]

After all the work on axles and hubs, it only makes sense to go coilovers.....oh and cut the existing control arms off and reengineer those as well.

Have I mentioned that we have a 7.25" ring gear? Frankly, I'm amazed mine has stayed in one piece. Those that remember my last break video will recall the front end having some good hang time... under power. I was SURE I was going to peel some ring gear teeth off when I hit. I didn't, I just broke everything else instead.

[Jrgunn5150]

I know this is an old thread, but that's what happens when you search. I am curious to get my hands on a lift and get in there and see what's going on and what can be done to stop the topping out issue.

If, say, the shock were 1" longer, effectively, would that do it?

[v7guy]

It's likely, stacking washers got the shock to live longer. It just needs to stop topping out so hard. You'll also have to verify the upper ball joint is still ok and the CV shaft is ok. Both are rather small issues.