Any recommendations on insulation? I've seen that stuff on Hot Rod TV they put in cars.

Thanks!

Ben

 

Hey Ben:

We *almost* found a way to get to the Ark to see you guys but just could not. A strange coincidence is that my son came to town here, left his car, and took our van to his college house in Ann Arbor (he's going to use it as main people carrier for the U of Mich mountain bike race up north in Grayling this weekend). So my van was within a mile of your show.

To enable PM, go to "User CP", then to Options, and I think there is a check box specifically enabling private messaging. (You don't have to enable E-Mail or anything else if you don't care to.)

It is sounding less to me like your problem is wheel balance. Insulating the van would definitely be a help. I know there are roads that seem to seem to make any vehicle shake and you're right that a 1 ton truck is not going to have a great ride. I once put some really stiff new shocks on a 3/4 ton GMC van and they made the ride worse, because they cut down suspension compliance. I've had big vans for 24 years running now.

With the van empty, you should probably try to reduce tire pressures and see how it feels, see if you still get the roof drumming, etc.

As a shot in the dark, what brand of tire are you using? I have had stellar luck with Michelins on my E150--the LTX M/S was the OEM tire, and I replaced them with the same thing after trying (and returning) another brand of tire. I'm only at ~42 lbs in the tires but I know that Ford used the LTX M/S on their big vans as well. Any tire with 80 lbs in it is going to be pretty stiff, but there can be a big difference between brands and designs. Likewise I have transformed a couple cars by moving them to MXV4 Michelins over the years. Tires are the first level in any suspension system.

I'm a bicyclist and have found that even with 25 mm wide road bike tires that I run 110-120 lbs of air in, a high quality, compliant tire can still give a velvety ride, whereas the cheapos ride like rocks. On a road bike, the *only* suspension is the tires so I certainly am very aware of road quality

George

 

What is your goal?

Accoustic? Thermal?

Price point?

Form factor?

Tell me all that first.

 

If your tire balance checks out, and roundness etc. all check out.

Leave it on axle.

Then check the balance ON AXLE and see if it is materially different.

Things like a badly out of balance rotor / drum can cause your symptoms.

Or ... bent drive shaft ... axle.

Manually rotate it... see if you can see something odd with the wheels lifted off ground.. but sufficient pressure on the springs to have it in a normal orientation.

 

Just a follow-up to the discussion, I got to spend a lot of time in N MI with this van on some exceptionally smooth interstate- with no vibration problems to speak of. After driving home, I started noticing how much most interstate road is slightly washboard in surfacing.

Combined with the flexing roof, I'm going to try some insulation next. Is there anything cheaper than Duramat out there?

Thanks,

ben

 

I dont believe in duramat.

If your goal is modest cost and sound, heat insulation, nothing beats fiberglass.

But be sure you have a vapor barrier on BOTH sides. Medium to heavy gauge plastic.

It must not trap moisture either way --- or rust will happen fast.

You got about 1" of room, about enough for R 5

If heat is a big deal, use aluminum foil on the side you want the heat to reflect back --- eg on the inside to reflect heat in.


If you are looking for something simpler, the bubble wrap that is foil covered works real good, but is expensive.

Low E Foil Insulation. Under Concrete Insulation. Reflective Insulation Radiant Heating. Under Slab / Under Floor Insulation.

It will not work as well at sound control -- it is primarily thermal.




Remove the headliner, install your vapor barrier, then fiberglass batts.

I used a temporary piecees of wire in between the ribs of the roof to hold it in.

then additional vapor barrier, and put the headliner back.

It will be good for about R-5 but will result in a noticeable quieter ride.

Do the same for the side and doors and floors ---

I strongly recommend you do not try to stuff foam into the empty cavities between the inside steel wall and the wheel well / outside.

Just add foam (in between vapor barriers ) to the outside.


If you did everything right, expect to see a sizable drop in noise levels.

3 to 5db is not out of reach.


FYI, I had a unique application of needing insulation for -40C to 25C operating temperature, so I added 1/2" wood to increase the insulation space to 1", at considerable expense to space.

But, If I put up my front "dam" and rear window insulation curtain, I am toasty comfortable at -40C with 10,000 btu heat.

 

Thanks, gearloose1, I'll look into this. Just to save time, I'm hoping that there is an aftermarket product cheaper than duramat to do this.

I'll also be looking up how to take the interior panels out, but this all may be superceded by the discovery of corroded coolant lines to the rear HVAC.

Many thanks for your help with this discussion!

ben

 

If I am not mistaken, the coolant lines as with the AC lines, are on the OUTSIDE of the vehicle, hung on the frame / underbody, not inside.

Replace them all!

Oh yes.. check the spring shackles on the rear of the springs --- they are often salt damaged.

Might as well chuck them, and toss in a new set of shocks if you are down there.

 

Hey, sorry to confuse posts! I need to investigate interior panel removal to damped roof "drumming" (George's term) and I'm going to be replacing the corroded coolant lines outside with heater hose very soon! Definitely two different issues.

ben

 

Interior panels and roof come off easily.

Start from the bottom (floor) === panels for side come out first, then the b pillars, then the roof.

Seat belts, etc. have to come out to remove panels

You probably want all the passenger benches out of it too.