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Discussion Starter · #1 ·
If you've ever driven a T4 lowered more than 50mm in the front you know how bouncy it gets, here's the solution to the problem.
The bounciness is caused by the upper arm hitting it's bump stop, and also even hitting the upper shock plate.

Start by getting your car up in the air(Dont forget the stands!)



Locate the lower shock bolt and undo it. Knock it through the shock, i didnt take it all out, sway bar preload may make it hard to get back in.



Locate the shock plate bolt and nut up top and unbolt them.



Shock and plate out!



Unbolt the shock, remove the bump stop and get to grinding! Remove most of the edge around the rubber bump stop.



Cut the bump stop down and it should look something like this.



A quick lick of paint for good looks.



Put it all back together and voila, lots of extra travel and you can lower the car mad low without the crashing and bouncing.

 

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When they're bolted back up, they effectively form part of the chassis rail so grinding off the 8mm lip doesn't compromise strength by a massive amount. And in any case they are mounting plates for the shocks and all the force is directed upwards and braced by the chassis. Loads of the low rider guys, including myself, have made this modification and I've not heard of one failing yet.

Mine........
 

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so when you compress the suspension to the bump stop the the shock load goes where? to the bump stop or bottoms out on the shock absorber and the shock load goes where?I think you underestimate the loadings on a 2.5 ton van, its built heavy for a reason
 

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so when you compress the suspension to the bump stop the the shock load goes where? to the bump stop or bottoms out on the shock absorber and the shock load goes where?I think you underestimate the loadings on a 2.5 ton van, its built heavy for a reason
I have short shocks, which don't bottom out. I'm not an engineer so am not qualified to press the point on a technical level. What I do have is bags of common sense. I did a lot of research and took a lot of advice from people far more experienced than I, before making any kind of structural mod. Trust me, safety is top of my agenda. I would not recommend something like this otherwise!
 

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When they're bolted back up, they effectively form part of the chassis rail so grinding off the 8mm lip doesn't compromise strength by a massive amount. And in any case they are mounting plates for the shocks and all the force is directed upwards and braced by the chassis. Loads of the low rider guys, including myself, have made this modification and I've not heard of one failing yet.

Mine........
that's the clip I copied to do mine, grinding the lip wont weaken anything as it sits and is bolted flush up against the chassis :ILU:
 

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Fair enough having not had a closer look at mine and seeing how it fits then I probably shouldn't have commented
No I think yours and Trism's comments are fair enough. Safety first, especially when lowering a van. But I've been running mine like this for over 2 years with no problem on a 100mm drop. I'm actually more worried about my lower ball joints! LOL:
 

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Good write-up; thanks for taking the time to do so. My US spec MV's bump-stops are nearly gone from cracking and splitting. I plan to do this modification. I have already run the torsion bar adjuster nut all the wy to the last thread or two. I'm hopeful that cutting the bump-stops will allow me to run the adjuster nut back up and keep some tension to the bars and perhaps improve the ride slightly. My biggest interest is the rear of the van. I have installed FK springs, which are literally half the height of the stock springs. I also have removed both upper and lower rubber isolator pads for maximum lowness. If I cut the front bump stops and lower the front further; how do I get the rear to match, when its already as low as I was able to get it??? Thanks
 

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Discussion Starter · #14 ·
That's exactly what i've done. With the stops modded and the nuts wound down the front dropped an inch and a half extra, while still allowing for some travel. Wound it back up a bit yesterday.
 

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Good write-up; thanks for taking the time to do so. My US spec MV's bump-stops are nearly gone from cracking and splitting. I plan to do this modification. I have already run the torsion bar adjuster nut all the wy to the last thread or two. I'm hopeful that cutting the bump-stops will allow me to run the adjuster nut back up and keep some tension to the bars and perhaps improve the ride slightly. My biggest interest is the rear of the van. I have installed FK springs, which are literally half the height of the stock springs. I also have removed both upper and lower rubber isolator pads for maximum lowness. If I cut the front bump stops and lower the front further; how do I get the rear to match, when its already as low as I was able to get it??? Thanks
Have a look at this

http://www.vwt4forum.co.uk/showthread.php?t=44312&highlight=project

Also you could look into air ride just for the rear. I'm not sure if anyone does kits for T4s in the U.S. So you might need to adapt something
 

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Is there a thread for doing the rear bump stops also as this is where I'm having an issue my van was lowered when I got it looking at the receipts it has -65 rear springs on it and the torsion bars on the front have been wound right out
 
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