Cub Shock Absorber Problems

[timsgonecamping]

Hi
I've had a few problems with the shock absorbers failing in the Cub camper (Supamatic).
I was just wondering whether others have had similar issues or is it just me.

Gone through 3 sets so far during the last 3 years.

The original yellow Ultimas went on the run through the Oodnadatta track/Merini Loop/Palm Valley.
Chewed out bushes and the weld at the top of the bell housing cracked.

Cub replaced these with silver Rox Shocks under warranty. They looked a bit stronger.
These went on the run to Cape Leveque. Again the bushes wore through and a bell housing weld cracked.

I replaced these with Monroes hoping this would fix the problem.
After the rest of the Gibb, Kulumburu etc they started leaking oil and one of the bushes is nearly gone.

So the question is whether this is to be expected or is there something wrong with the geometry of how the shocks are set up on the Cub.
I have independent suspension on the Cub. The shocks aren't in line with the springs but lay back at an angle towards the rear so there must be some twisting as they absorb shocks.
Maybe that's why the bushes get chewed but it doesn't explain the rest of the problems.
I know the roads were corrugated but they were all in fairly reasonable condition.
I more expected that I would have problems with the Prado shocks, since they are just the standard factory ones, but they were fine.

So I'll replace the Monroes with something else (any suggestions) however I would prefer not to have to replace them after every trip.

Thanks
Tim

[thommo19]

Hi Tim
I own a cub myself and have found them to be very good on service.
I would be going back to Cub for an explanation.
Jeff

[armbrup]

Has the Cub got bump stops?
I have a 1997 Camp'o'matic which was the first with independent suspension. Camp'o'matic are a different manufacturer than Cub as they started together but separated in AFAIK the 1980s.

It was fitted from new with Koni shocks and these lasted about 15 years before I noticed a deterioration.

I replaced them with new Konis when the Koni agent said my old ones had damaged foot valves from bottoming , even though my Camp'o'matic has large progressive bump stops.

The Konis have now been around Oz including 1000Km of dirt on the GRR with no problems.
You cannot rely on the internal stops of shocks on a camper trailer.
I recommend Konis.
Regards Philip A

[timsgonecamping]

Hi Jeff
I intend going back to Cub to see what they say.
Just thought I'd do a bit of research first to see if it was just my one or more of a general issue with the Cubs.

The Cub does have bump stops Philip. Two fairly small rubber pads but they do stop compression travel.
However there isn't any restraint on extension travel. I've heard of some campers having straps to limit how much the shocks extend when the wheel drops in a hole.
I would stay the Cub just relies on the springs to provide some resistance to extension. Maybe a possible cause of problems.
I'll have a look at the Konis.
Tim

[robcaz]

Hi Tim,

Perhaps the shocks are too long??? If the shocks bottom out before the coil suspension is fully compressed, you can damage the shock, bend shafts etc. To check if this is happening I would jack under one side of the independent suspension to fully compress it, making sure you support the frame so it does on move if the jack slips, & measure the shocks compression eye to eye or similar as a reference.

Remove the shock, get Julie to compress it & remeasure to make sure the coils are compressing fully before the shock does.

The rubber bushes also need to be compressed to some degree when tightening the shocks nuts. You might want to enquire to Cub what torque they recommend. If they are not torqued correctly the shock can move around in the housing & cause problems, often chewing out the location brackets hole.

Jeff Pethybridge did have trouble one his Cub's leaf suspension shocks hitting the cross member & he redesigned the shocks brackets. Check "Jeff P';s Mods /Pics" album in the Photos section of the CamperTrailers Yahoo Group for photos.

Our Track Trailer Eagle has 60 series Landcruiser leafs with very short shocks that are from the front end of a Land Rover & positioned horizontally rearwards at about 45 degrees. A photo of the righthand shock http://i145.photobucket.com/albums/r222/robcaz/left.jpg

[armbrup]

The Cub does have bump stops Philip. Two fairly small rubber pads but they do stop compression travel.

As the previous poster said , you should check that the suspension bottoms on the bump stop before the shock is fully compressed, and you should check that there still enough movement in the shock to let the bump stop compress to half its thickness, as they do that.

The way to do it is to undo the shock, jack up the BODY until the spring can be removed , then move the suspension by hand with the shock connected.

On rebound the shock is what stops the suspension droop with coil springs and my Camp'o'matic has chains wrapped in plastic to prevent the shock topping out. This may be your problem.

Camper trailers are hard on shocks so you need good ones and to look after them so that they are just acting as shocks and not suspension limiters.
Regards Philip A

[Ern_Reeders]

Yes, my Pioneer IS has straps to limit topping out.

But chewed out bushes and weld breaks sound like a geometry problem to me.

[timsgonecamping]

I agree that there does seem to be a geometry problem. However it's a standard Cub arrangement.
Apparently some have this problem and some don't. Same model, similar travelling conditions, so not sure what the problem is.
Cub have offered to have a good look at the camper to see if they can spot a problem, which is reasonable of them since it's well out of warrantee.
So I'll see what they find.

In the mean time I'll have a look at whether the bump stops are doing their job of restricting travel to protect the shocks.
And make sure I carry a spare or two.....

Tim