Its Brian from Adelaide here and I am seeking some input from other Coromal owners in regards to a couple of issues that I have encountered since taking delivery about 4 years ago.
During our recent journey to WA I noticed that the front near side tyre started to chop out on the inside edge. I had the tyre turned on the rim and noticed at that time that the bottom spring leave had broken. The Caravan place which happened to be right next door to the Goodyear tyre place fitted a second hand spring leave and pointed out to me that the front axle had a 4 leave pack and the rear axle has 5 leave packs. Does anyone know if this is normal and why this might be so? And of course, would the broken spring leave have been the cause of the tyre wear? As Coromal are no longer in business I have had no success in getting advice through them or the people that purchased the brand.
I would love to receive some feedback,
kind regards, Brian
yobarr said
06:42 PM May 30, 2023
WBD wrote:
Good afternoon members.
Its Brian from Adelaide here and I am seeking some input from other Coromal owners in regards to a couple of issues that I have encountered since taking delivery about 4 years ago.
During our recent journey to WA I noticed that the front near side tyre started to chop out on the inside edge. I had the tyre turned on the rim and noticed at that time that the bottom spring leave had broken. The Caravan place which happened to be right next door to the Goodyear tyre place fitted a second hand spring leave and pointed out to me that the front axle had a 4 leave pack and the rear axle has 5 leave packs.. Does anyone know if this is normal and why this might be so? And of course, would the broken spring leave have been the cause of the tyre wear? As Coromal are no longer in business I have had no success in getting advice through them or the people that purchased the brand.
I would love to receive some feedback,
kind regards, Brian
Hi Brian. The set-up you describe is NOT normal. The Coromal system ,know as Symons Knee Suspension, is not a load-sharing system so van MUST be level. Parts can be obtained from Melbourne Trailers who have re-named the suspension using their own name. Spring packs are almost impossible to source, as they are 'slippers' at both ends, and finding someone to build them will be a mission.
With 4 or even 5 leaf suspension I suspect that your van is a lighter model, possibly up to about 2300kg ATM? Because of the lighter spring pack your front axle has, the wheel goes up closer to the chassis, causing negative camber and obviously tyre wear on the inside of the tyre. The more weight you put in the van the greater is the spring compression and resultant negative camber.
That ATM figure can be found on your compliance plate, inside your van's front boot. If you can post that we may get an idea of what's going on!
The spring packs are sold as 7 leaf units, which I have, and you simply remove leaves to create a spring that suits your van's ATM.
This should give you an idea of what's wrong, but I suspect that the 5 leaf springs you have on your van were fitted after the original 4 leaf springs broke. I'd be installing 5 leaf packs on the front axle to match those on the rear.
Sounds complicated, but it's not. The suspension system you have is the only type that has NO axle steer. Cheers
P.S If you have no luck sourcing spring packs I may be able to help.
P.P.S Derr! Just looked again at your post and saw that your van is a 612 so original springs would have been 5 leaf, I'd say.
The 4 leaf springs were fitted for who knows why, but they're too light, causing the tyre wear discussed earlier.,
-- Edited by yobarr on Tuesday 30th of May 2023 06:51:10 PM
Thank you Guru,
I appreciate your comments and tend to agree with you. I bought the van new and the only reason that I can think of for the 4 spring set up is to allow for the vans tendency to push down onto the towbar causing the van not to be level when hooked up to our Prado.
I will talk to Melbourne trailers tomorrow to see what their thoughts might be.
Thank you so much for sharing your knowledge.
Regards
Brian
Possum3 said
09:24 PM May 30, 2023
Just a thought WBD - usually a scrubbed tyre on the rocker springs signifies a bent axle. You may need to go to a heavy vehicle specialist (Truck suspensions) to have an alignment done.
Good afternoon members.
Its Brian from Adelaide here and I am seeking some input from other Coromal owners in regards to a couple of issues that I have encountered since taking delivery about 4 years ago.
During our recent journey to WA I noticed that the front near side tyre started to chop out on the inside edge. I had the tyre turned on the rim and noticed at that time that the bottom spring leave had broken. The Caravan place which happened to be right next door to the Goodyear tyre place fitted a second hand spring leave and pointed out to me that the front axle had a 4 leave pack and the rear axle has 5 leave packs. Does anyone know if this is normal and why this might be so? And of course, would the broken spring leave have been the cause of the tyre wear? As Coromal are no longer in business I have had no success in getting advice through them or the people that purchased the brand.
I would love to receive some feedback,
kind regards, Brian
Hi Brian. The set-up you describe is NOT normal. The Coromal system ,know as Symons Knee Suspension, is not a load-sharing system so van MUST be level. Parts can be obtained from Melbourne Trailers who have re-named the suspension using their own name. Spring packs are almost impossible to source, as they are 'slippers' at both ends, and finding someone to build them will be a mission.
With 4 or even 5 leaf suspension I suspect that your van is a lighter model, possibly up to about 2300kg ATM? Because of the lighter spring pack your front axle has, the wheel goes up closer to the chassis, causing negative camber and obviously tyre wear on the inside of the tyre. The more weight you put in the van the greater is the spring compression and resultant negative camber.
That ATM figure can be found on your compliance plate, inside your van's front boot. If you can post that we may get an idea of what's going on!
The spring packs are sold as 7 leaf units, which I have, and you simply remove leaves to create a spring that suits your van's ATM.
This should give you an idea of what's wrong, but I suspect that the 5 leaf springs you have on your van were fitted after the original 4 leaf springs broke. I'd be installing 5 leaf packs on the front axle to match those on the rear.
Sounds complicated, but it's not. The suspension system you have is the only type that has NO axle steer. Cheers
P.S If you have no luck sourcing spring packs I may be able to help.
P.P.S Derr! Just looked again at your post and saw that your van is a 612 so original springs would have been 5 leaf, I'd say.
The 4 leaf springs were fitted for who knows why, but they're too light, causing the tyre wear discussed earlier.,
-- Edited by yobarr on Tuesday 30th of May 2023 06:51:10 PM
I appreciate your comments and tend to agree with you. I bought the van new and the only reason that I can think of for the 4 spring set up is to allow for the vans tendency to push down onto the towbar causing the van not to be level when hooked up to our Prado.
I will talk to Melbourne trailers tomorrow to see what their thoughts might be.
Thank you so much for sharing your knowledge.
Regards
Brian