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I have a merc 670 L.W.B diesel Hymer which goes well. A couple of things I was wanting info on.
1. She is a bit wallopy on cornering especially fully laden and was wondering about uprating springs or fit air units to suspension. .where can I access equipment needed.
2. Very high revs in 5th gear and would consider going up a gearing in rear diff. She is whining and may have to take diff. out anyway.

Many thanks to anyone who can help
Rab
 

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air bags are the way to go they'll sort that wallowing out best, thing i did was fit them, i made up my own, but you can get them from a company called airide have a google up and see, don't know about gearing sorry. dennis
 

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what merc?

Yes we need to know the base chassis, but from your comments I assume its an older Hymer probably a 410D as used in the S680 and my S700.

Yes the gearing is too low in 5th - a common gripe. I have seen a few comments about it over the years. There seem to be 2 solutionms. One is change the rear diff ratio, but this would affect all the gears- and I have never actually heard of anyone doing it, not even sure if theres an alternative diff available, but would assume with money, there must be a firm somewhere that could machine and fit new diff gears.

The other, and more popular option is to fit bigger wheels and tyres. This is reputed to improve things nicely, but finding the right wheels is the problem, especially if you have double back wheels.

If successful this gives you about 10% increased rolling diameter, and doesn't seem to mess up the drivability through the gears.

there seems to be a fair amount of compatibility across the merc range of wheels. I have been told that merc 609 wheels fit and also some 15" wheels from the sprinter range.

I myself am researching fitting bigger wheels to my 410D

However this will not solve the whine....which is also pretty characteristic and also old age. Also be sure that it is the diff and not the propshaft. They are famous for singing prop shafts, and I have been told that the way to cure this is to inject expanding builders foam into the hollow shaft.

Hope this helps

Ron
 

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suspension

Oh and about the suspension. Airides are popular but expensive.

If your van is old, the first thing to dois to check all the leaf spring retaining U bolts are present and correct. After many years I was finally told that all mine had broken and when they were replaced it was miraculous!! Uprated rear springs are an option, and cheaper than airides, as are uprated shocks.

Airides are the accepted solution, but make sure your suspension is in good order first. Merc Hymers are solid, but pretty much permanently fully laden so you have to maintain the springs and shocks.

Ron
 

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re-gearing the 416 diff is certainly possible. Replacement crown and pinion are available from Italy, I will dig the info out.
The other option is to find a Minibus diff (Merc fitted the lower/higher ratio)
on the minibuses as they expect them to do more motorway than the vans.
So I guess a look around the reclaimers may be worth a punt.
I was quoted about 130 euro for the crown / pinion then about 300 quid for a diff rebuild using the above. Havnt done it yet as the UK rep for the gear manufacturer is a bit pants !
 

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got a merc 2009 length 7.45 Metres with rear garage keeps bottoming out even with a half filled garage has any one had the same experience?
if any one has , how was it rectified is it a possible fault
 

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Air Suspension

I fitted Air Assist to my Merc. Two systems are avaiable "Dunlop" & "Firestone". I have fitted both with no problems.

I would suggest you look at specification tables and shop arround as I eventually purchased a set of Dunlops for about £100 less than the originally quoted figure.

Steve
 

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Air Assist

I have looked all through my records but the invoice for my system is missing so I am reliant on memory. The kit I finally purchased was from Marcle Leisure. I found the gentleman here most helpfull in getting the specification correct.
What I cannot recall in detail was whether the price saving was for the same kit but different suppliers or when comparing Firestone against Dunlop. Sadly I have removed the list of suppliers from my computer.

My van is based on a 2002 316CDI Sprinter and the kit fitted is for the 200/300 sprinter or VW Lt28-35.
I hope this may help a little.

Steve
 
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