Mud-club
Vehicle & Technical => Discovery => Topic started by: disco-v8 on May 31, 2009, 23:41:22
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ok my dad uses his disco to tow alot, and will be needed to tow my disco to events soon, so he has slowly been buying new running gear for it bit at a time.... hes already got new springs and shocks for the rear, which have been changed to the yellow heavy duty ones, as its to helphim with towing....
he now wants to match the front end with the rear by getting heavy duty springs and shocks, as he thinks it will help him out with towing.... fair enough no extra weight is going to be added but he thinks it will be better than the standard crap hes got on, plus will better match hes polly bush kit....
so question is..... is it a good idea to upgrade the front suspension to heavy duty springs and shocks or not???? what will all the pros be if he has it done, and what will all the cons be????
oh and another thing, will it affect the way it drives
thanks :thumbup:
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I have a full poly bush kit with the same HD +2 yellow springs all round and it made the whole car just feel more planted to me,but im running with standard shocks so cant answer your question fully.Bear this in mind though my springs that were on there were shot to bits so im unable to give you a comparrison between the 2,well an acurate one anyway.One thing I know is that I wouldnt swap them back to standard.The only thing that my springs changed was I lost some articulation and it doesnt roll as much in the corners and the ride was a little stiffer but not noticeble unless you knew you had changed things(well the mrs never said anything and shes usually the first one to complain).
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Mine's an ex-family towcar (passed to me when Dad got a company car) so I'm not sure if that has affected my findings.
Generally I find that the standard front springs are too stiff, or the rears too soft. I often end up with a front left wheel in the air while scrambling up rocky bits as the back end just sits down and allows the front to lift. Mine has had the sills professionally rebuilt with 4mm steel, also has a heavy recovery gear box in the boot along with a full tank of diesel and a hilift on the back when laning.
The back end flexes superbly, but I reckon it would still flex with stiffer springs while forcing the front end to flex more, if that makes sense? I also have a winch bumper waiting to go on (when the sellers get back to me about the fact that it doesn't fit properly) which should add a bit of ballast to keep the front on the deck, even without a winch.
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I have standard hight heavy duty springs and gas shocks all round ,with poly brushes,it sits well and the ride is furm but in a good way.The only trade off is you might loose some slight articulation at the front.
I use mine for towing horse boxes at the weekend and I intend to fit a winch to the front end in the future so I thought it might cope better with the extra weight.
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Generally I find that the standard front springs are too stiff, or the rears too soft. I often end up with a front left wheel in the air while scrambling up rocky bits as the back end just sits down and allows the front to lift. Mine has had the sills professionally rebuilt with 4mm steel, also has a heavy recovery gear box in the boot along with a full tank of diesel and a hilift on the back when laning.
What is it like though at other times, such as level axle twists, side slopes and decents?
Due to the high centre of gravity, when you climb up something the centre of gravity moves closer to the rear axle, making it heaveier and the front lighter. In a decent the rear will become lighter an the front heavier. A compromise has to be reached, if you made the rear stiffer and the front softer to make it more suitable for ascents, then it would become less suitable for decents.
During an ascent the weight is transfered to the rear axle and significant part of traction is proportional to weight so the rear axle will be doing most of the work anyway rather than an even distrobution between front and rear.
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Thankfully it seems to be fine on sideslopes (good, as I start getting very edgy at about 30 degrees and will not go beyond 40!)
I've not really tried axle-twisting, but it does seem to behave well on level or downhill parts. I know I can just trickle it down loose rocky bits without any fuss beyond maybe a few stones popping out from under the wheels.
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Digressing back on topic. ;)
Putting HD springs and shocks on the front for general towing might help but then might not. Yes for the back end as you will have the extra weight of the trailer nose weight, pushing on the back end. In this case the front will be slightly lesser weighted anyway. So the Stiffer springs might cause the steering to become twitchy and edgy when going along. something you don't want happening. How? Well i look at it as the disco with a proper trailer up behind with a good load on it will sit slightly nose high due to the weight on the back. Now HD springs have a higher spring rate and so will not compress as much as standard springs, Now with the disco being effectivly lighter on the front because of the trailer the HD springs will exacerbate the noise in the air and as the same with a suspension lift kit too much and it starts to affect the castor angle which upsets the steering.
IMHO a Towing vehicle needs all the bushes to be pukka with HD Springs and shocks on the rear if towing all the time or just the shocks for occasional towing jobs. Standard springs will sag with age so maybe just new standard fronts coupled with the HD rears and Decent shocks all round should provide a good ride.
Remember that unladen any vehicle on HD suspension will ride very harshly and this is something that many overlook when choosing new suspension for their vehicle. The best way is to look at what you have and what you want to do. Work out the loads and the weight you will carry. With this you can look at the manufactures options with what spring rates they have to match your demands.
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How? Well i look at it as the disco with a proper trailer up behind with a good load on it will sit slightly nose high due to the weight on the back. Now HD springs have a higher spring rate and so will not compress as much as standard springs, Now with the disco being effectivly lighter on the front because of the trailer the HD springs will exacerbate the noise in the air and as the same with a suspension lift kit too much and it starts to affect the castor angle which upsets the steering.
:-.
Assuming these are stiffer, but standard ride height springs, then the nose should rise less when the trailer nose weight acts on it. The weight transphere from front to rear axle is to all in tents and purpose the same, and the stiffer rate means the springs extend less for a same ammount of weight being transphered off them.
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I have the heavy duty springs and dampers all round on mine and helps body rol alot. Never had a problem off road and tow a twin axle caravan. Ok the caravan didnt tow very well but I put that down to the caravan as it doesnt tow well behind my new tow car either. :evil:
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Definitely do the shocks, keep the car balanced. Not sure about the springs, check that the H/D ones are heavier than the originals, I'd be tempted to fit new original equipment spec TBH unless you are adding weight.