Bump stop options?

[d.p]

I am lowered 3" blocks in the rear and re-indexed one spline in the front w/KYB gas shocks and the ride is OK on a smooth road.  A bridge is torture and any bump in the road or pothole is not fun, its livable but I would like make it more livable.   

 

What are my options besides raising it back up?  Do they make adjustable bump stops for a 521?  Cut/trim or remove them completely?  C notch?

[banzai510(hainz)]

there s rubber stop up front and you can remove it with a 12mm or 14mm.

 

otherwise raise it back up.

 

your lowprofile tires dont absorb alot of shock , thats why I like the stock set up. but just lowered

[d.p]

What about cutting rear bump stop?  Will that alleviate it at all?  

[banzai510(hainz)]

I  HACK SAWED MY RUBBER STOP OFF . Well most of it.

The rear should not bottom out  if your carrying nothing.   Cuase I have 3in block in back also. and actually use it for dump runs.

[datzenmike]

This is what you have to put up with on a too lowered vehicle. You have to have some suspension travel in order for the shock absorbers to absorb bumps. If you are on a squashed bump stop then you have almost no suspension movement. Your tires are the suspension, a rubber ball bouncy suspension. You can try cutting some of the bump stop off and the truck will likely lower some more. If you raise it back up to before you cut it height you will have a slight increase in travel. (don't expect miracles though) Keep in mind that on a lowered vehicle too much suspension travel will result in bottoming out.

 

Lowering changes a vehicle's utility or function. Within reason it improves handling, but unreasonable lowering all comes down to a shitty ride and underside damage for a 'look'. Classic form over function. The young tend to go too low because looks are more important than ride quality.

[d.p]

I  HACK SAWED MY RUBBER STOP OFF . Well most of it.

The rear should not bottom out  if your carrying nothing.   Cuase I have 3in block in back also. and actually use it for dump runs.

 

How much you cut off?  Fairly certain mine is riding on them now.  

[banzai510(hainz)]

I hacked all the rubber off If I remember right.

[Stoffregen Motorsports]

Cut off what you need to. Or start by cutting a little bit and gradually work up to what feels best. You need to have something besides metal on metal or else you will end up hating the truck very quickly.

[wayno]

It really depends on if your talking about the front or rear and how low you are.

The rear has a large rubber piece that looks like an "8", you can cut the bottom of the "8" off and it will be a small "o" then, but most remove them all together if going real low, if real low then a "C" notch is the only real answer.

The front is different, you can take out the bump stop and cut some off of it, but there really is not a real low solution that keeps the ride unless you start modifying things, it's a lot of work to go low in the front, and there are disadvantages/drawbacks, the main one is you start hitting that cross member below the oil pan and the cross member where the torsion bar adjustment is, the exhaust starts dragging, and the frame starts dragging on everything.

Mike Klotz has made drop arms for the front in the past(320/520/521/early 620), it's like drop spindles for the kingpin frontend, you can also raise the front shock tower mount, but in the end the front/frame is going to start hitting/dragging on all the speed bumps, manhole covers that stick up even an inch, even a dip on the hiway can get the front cross member under the oil pan, heaven forbid someone looses there trailer hitch on the hiway and you come along and catch it on your underside.

It's a lot of work to go low safely, I have one low one(my 520 ute), I will not do that again, I had to raise it an inch just to get in my own driveway without dragging the frame, and my driveway isn't that bad, by the way, parking lot speed bumps are a bitch.

[d.p]

Not trying to slam it, just want to take some of the bounce out after lowering it.  I will cut the 8 in half in the back and see if it helps.  

[banzai510(hainz)]

try the stock rims and see how it rides

[G-Duax]

Shorter suspension travel due to lowering demands stiffer shocks, and I doubt KYB gas qualify.

They are designed to give a reasonable ride with stock travel. Take away that travel distance, and you will be bouncing off the bump stops.

 

The only way around it is to modify the rear frame rails to allow more travel at your intended ride height, and drop spindles, which are almost impossible to find for the old king pin front ends.

[Loryde520]

My dentist likes me! I've gotta get new fillings every few weeks. I'm on a static lower and I am seriously contemplating air-ride. 

The back rides fine on 3" lowering blocks snubbers removed. Front was re-indexed on one spline drop, no snubbers. The problem is you really need shorter front gas shocks. I am running a little bit shorter old stock KYB. I also had to camber in my front end for tire to fender clearence.

[distributorguy]

Its paramount to make sure the shocks have ample travel before sorting the rest out.  You can remove all the snubbers and still have the shocks hit bottom hard.  Part numbers are in the archives here if you do a search.

[d.p]

I got KYB gas shocks already, you talking about getting a shorter set?   If so anyone got a link?

[datzenmike]

You sure the shocks are going to bottom out? Why would Nissan design them to bottom out before the suspension did? When the LCAs are beyond the bump stops you can't expect ANY shock absorber to be doing any worthwhile dampening. There just isn't enough travel to soften the blow and this is why your dentist loves you. Replace the tires will softer or fewer side wall plies. Car tires rather than truck tires.

[Royal Sierra]

I have 3" blocks with 2 leafs pulled and my shocks dont bottom out in the rear. Also the rear bumpstops are only held in by 2 bolts on each side.

[datzenmike]

Removing leaves is risky for lowering a vehicle. For one it allows even more suspension travel on an already very low ride height. If anything you want less travel and stiffer to avoid bottoming out. The other is... the leaf spring pack is what supports and centers your axle and prevents side to side movement and tire rub under hard cornering.  

[Loryde520]

You sure the shocks are going to bottom out? Why would Nissan design them to bottom out before the suspension did? When the LCAs are beyond the bump stops you can't expect ANY shock absorber to be doing any worthwhile dampening. There just isn't enough travel to soften the blow and this is why your dentist loves you. Replace the tires will softer or fewer side wall plies. Car tires rather than truck tires.

Yup, I am running very nice car tires on steel wheels.

[d.p]

Not going to switch my tires or wheels at this point.  Will trim bump stops and see where it gets me.  

 

I have seen some adjustable ones for 620/720s from summit but don't think anything like that exists for 521s.  

 

https://www.summitracing.com/parts/ENS-9-9102R/?rtype=10

[Crashtd420]

Energy suspension has a ton too. not specifically for 521 but all types and universal ones. I planned on just seeing what looked like it would work and just making it work ... all your trying to do is prevent the metal parts from contacting...

[d.p]

LMK if you find one that works with 521s. 

[Crashtd420]

Ya I haven't really made a decision on mine, hell I don't even have shocks yet but it's something I will have to deal with eventually too ... I'll poke around and see what I can find... running out of things to look up when I get bored anyhow...

[d.p]

Alright revisiting this now.

 

Rears:  http://www.energysuspensionparts.com/191306

 

And for the fronts I found these with a review from someone with a 521:  http://www.energysuspensionparts.com/9.9102

 

My truck is riding on all 4 bump stops and I am trying to get the rear driver side off but the inside nut/bolt seems to be seized up.  It backed out a lot but froze up towards the end.  Was going to try and cut them but would prefer not to unless I have another set lying around (like to keep stock parts) and they seem to be hard to come by.   So I figure I can just swap them all out and see how it rides.  

 

Rear mounting holes on the frame are 5 1/2"s apart so the above should work just fine.    

[wayno]

On the rear the bump stop looks like the number "8", just cut the lower half of the "8" off so it is a short "o", that will give you some extra room right there.