Friday, November 13, 2009

Road Trek - Lifting a 94 Dodge Van

A friend of mine recently purchased a Road Trek Class B motor home. It is built on a 1994 2wd one ton Dodge Van chassis. The coolest thing about this little camper is just that: it is little. It is the size of a full size van, yet it is completely self contained: hot water, shower, toilet, stove, furnace and fridge. Cool as it was he complained that it would bottom out on the smallest of bumps. What condition are your shocks in?: new. I was doubtful that it was actually "bottoming out". Worn out suspension components, such as ball joints will often cause a clunk which could feel like the suspension hitting the limits of its travel. However upon a visit to his place reviled that in fact his suspension could be BO.


The suspension appeared to have sagged, though the tell tale negative camber of lowered cars or those with sagging springs was not present. However the lower bumper stop (B) was less then 3/4 of an inch from resting on it's stop. Comparing the the available travel for compression (C) verses the allowable for rebound (R), shows that at the vans current ride height an estimated 25/75 ratio of compression/rebound existed (that is being generous, in fact it seems like it was closer to 10/90). 50/50 is more typical with some more aggressive sets ups at 75/25. In the picture to the right you can see both the rebound (UB) and compression bump stops. Notice the deformation of the lower bump stop from repeated bottoming out.

This last time my friend came to visit he drove his Road Trek out. Naturally I wanted to help him fix his BO issue. I figured a new set of OEM springs were the best solution. I wanted to install some lift springs to gain him some extra lift but was afraid that such a modification could lead to fitment problems, misalignment, or a harsh ride. Better leave it stock for this weekend job on someone else's rig.

I had spent some time looking for a reference on the spring replacement. None were found. I guess Dodge van owners just drive around sagging.
The front suspension is a double arm coil spring over shock set up. The coil spring sits in a bucket within the front cross member/frame. The lower control arm holds the lower half of the spring in place. The shock runs though the middle of the spring, attached to the frame on one end and through a pin bolted to the lower control arm on the other. Though the the shock run through the middle of the coil spring, these were not consider "coil overs" because they were not attached together, each attaches to the frame and the suspension via its own mounting location. The lower arm is a single pivot modified channel, with a compression rod.


My original intention was to disconnect the lower ball joint from the knuckle and drop the lower control arm. This was more difficult to do then I imagined. The lower ball joint sat tightly in its tapered fit and did not want to separate. I could not get a separator tool in there due to the tight fit. Though I started hammering a pickle fork into the cavity I soon stopped cause I did not want to ruin his ball joint or BJ boot. Instead I removed the upper control arm mounts. The UCA is a dual pivoting "A" on a cross pin. The pin is attached by two bolts to a brackets on the frame. Once removed I "flipped" the entire assembly down and freed the LCA, which still had the knuckle, brakes, and UCA attached to it. Once the LCA was free we were able to pull out the coil spring. The UCA cross pin bolts to slotted holes in the bracket, the positioning of the pin is responsible for camber and caster adjustments. Be sure to mark the location of the cross pin in relation to the frame/brackets prior to removal.

Comparing the new spring with the old springs was not very satisfying. They were the same height. I just hope that the break down of the spring was caused by metal fatigue and was not visible. The new coil was not exactly the same as the older one either. The windings of the coil were tighter.
The first side took us 3 hours to do. The second side 20 minutes. After we tightened the last bolt and lowered it to the ground I took an "afterwards" measurement. The van sat almost three inches higher. After settling, I figure we would have gained two inches of height. Test drives proved that the spring replacement was a success and the van no longer bottomed out!
Below is a step by step procedure for spring replacement:
-Jack up vehicle
-Set on jack stand
-remove wheels and set underneath the frame
-Mark upper control arm cross pin location
-remove two brake line brackets
-remove shock lower mount (two bolts on a small cross pin)
-remove bracket holding the lower bump stop, compression rod, and sway bar
-unbolt upper controller arm cross pin
-unbolt shock upper mount nut
-remove coil spring
Installation is the reverse of removal (ha ha, I hate it when I read this in repair manuals, but it basically is). The most difficult part is to reattach the UCA. The bolt and large nut on the cross pin in particular. You can reach behind and lift the nut in place, or attempt to shim the nut into position and fish for threads with a too short of bolt. A second set of eyes looking through the open hood is needed to align the cross pin back in position.
And there you have it one Dodge 1 Ton Van lifted two inches!!

12 comments:

  1. Sweet!! We are glad you are getting practice working on dodge vans. If we have any van trouble we know where to go. :) Any experience with replacing the tranny? j/k :)

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  2. Thanks for posting this. I just picked up a battered old '73 Dodge can and this is one of the mods I'm planning.

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  3. Did you check to make sure the break liness are long enough for full extention. 3" is a lot it'll probably need an alignment with that much difference. Good work!

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  4. Though I "lifted" the van I basicly returned it to stock height, so the brake lines should be fine. When on jack stands the suspenions was at full droop, and they were fine. And this type of lift simple redistributes travel stroke to allow for more compression, the full cycle length was not changed at all.

    I was a bit concerned about aligment. FOr those reading this, I would reccomned an aligment afterwards, not just cause you monkeyed with the setting, but you changed the ride height so much. But... Aligments are a rip off. SO instead this is what I did. To begin with the suspension set up has very little camber change through its travel. This is a good and bad, but a topic worthy of its own post. So without dramtic camber changes, the toe angle does not change too much either (assume no change in caster). Prior to any work I took a rough toe measurement. With a tape measure, measure the distance between the front of the left and right tire and the back. This distance did not change after the work was complete. A test drive did not yeild any funny pulling of the suspension either. I told my friend to keep any eye out on tire wear and none was found. So we concluded that an aligment was not needed.

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  5. I could use some help.....I have a 72 Dodge B200 Maxivan. The front sits pretty low.
    I'm wanting to put some 32/11.5/15 tires on the front. I have that size on the rear along with some 3 inch lift blocks.
    But back to the front. I think I'd like to lift the front end 3 or 4 inches in order to fit those tires in there.
    I've been looking for longer springs.....but am also considering spring extensions....But I just looking for suggestions.
    Pete

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  6. If you want help faster, e-mail me directly. Id on't always check the commnets section. One thing to keep in mind is that lifting doesn't always allow you run bigger tires. Most of the time, the lift I discribed just resets the resting postition of the suspension to a higher location. The suspension still cycles the same path. Thus when you bottom out the suspension your tires will still rub. I am of course of the school of thought that you should bottom out the suspension sometimes, otherwise you are not using the entire travle.

    Without knowing the details of your suspenion set up, I will assume that you have an independent with coil springs over a shock. A newer spring with a slightly heavier duty spring rate would most likey freshen up the front end quite a bit. There are also many generic coil spring pads that will gain you a little bit of lift.

    As for mounting the larger tires. THe best thing to do is to trim a little bit of the body around the wheel wells. Then covering the tirming up with some fender flares. You can find small flares that look OEM. You can most likey do a small body lift that will allow you to accomidate larger tires. But body lifts are not without their share of negatives.

    Go ahead and e-mail me if you want to talk lifting more.

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  7. Re: lifting the van,
    Are lift spindles available? It seems like that might be a decent/safe alternative. Perhaps there is s 2wd dodge pickup with spindles located lower on the arm to provide lift?

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  8. I would not think that a set of lift spindles is a better alternative than simply returning the vehicle to stock height. Remember that in the sagged condition the van barely had any bump travel and would hit the bump stops simply by exiting a driveway. It would have been foolish to install lift spindles, if available, onto the van in that condition. Now if one corrected the suspension and wanted addtional lift, that is anyother story.
    As for an acutal product, I never researched it. Though it seems very possible that a set of lift spindles were created for a Dodge 2wd truck which shares the same suspension set up.
    Please post if you find such a product.

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  9. Really a good post.Very informative article. I need about a snöslunga repair article.

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  10. Bill,

    thank you so much. Every other article I've read so far has the installer popping out upper and lower ball joints to get in there to replace the coil springs on the same van, which I have.

    Thank you so much.

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  11. Bill, what did you use to compress the springs for the rand r?

    I almost did a dry run practice on a junk yard van today although real deal im going to put in prefab new a arms with bushings and ball joints already in place as complete assemblies.

    thans.

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  12. How do you manage to fix your car problem by own? Though few of car issues can be resolved by own but I don't think the major problems should be made a try by own. I read the whole procedure that you have elaborated here but I could not understand anything out of it. I suggest, you should take the help of a good van repair specialist. You may prefer Sprinter Van Service Eugene, OR. I guess it would be helpful to you.

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