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Hampton Caught
20th August 2007, 17:02
That got your attention! :D

Whilst loaded up for my holiday with four bikes, stuff, family, stuff and a caravan, full of stuff, I had concerns about the height (or lack) at the rear of the car. Strange that! The Witter detachable towbar didn't help as this finishes some inches below the bumper, unlike the Brinks towbar.

As well as bottoming out on the caravan park speed bumps (placed just below a steep incline which I climbed out of with much wheelspin :rolleyes: ) I also noticed that the camber of the rear wheels was even greater than normal. Having had to replace the first set of tyres at 11,500 miles, I don't fancy another set so soon - the inside shoulder of the rear tyres were bald.:SHOCKED:

I'm left with two options (or a third if you include my wife's suggestion of another Land Rover instead of the MG :cry:).

Option one, spring assisters, cost about £15 (I live near Grayston's so can collect them) and are a DIY job (apparently).

Option 2, self-levelling suspension :) . Can anyone advise me what I would need to have the factory set up for my ZT-T, which is a facelifted model with the CDT engine? Is it DIY and would I need the four wheel alignment set up again afterwards?

Very many thanks,

Steve

JohnDotCom
20th August 2007, 20:08
The self-leveling I have on my R75 Tourer is just a question of changing the Dampers and possibly the springs I believe.
I had mine changed to self leveling with Genuine Parts and it was a straightforward job.....
Not for me but for the garage that did it, took them just over an Hour. Then the Alignment and tracking was checked 4 Wheel Laser.
For codes see here: http://www.the75andztclub.co.uk/forum/showthread.php?t=104

Lovel
20th August 2007, 22:24
If you want to change from conventional units to self levellers, here are the part numbers you require.
RKB000370 Spring x 2
It should be noted that the softer rated self leveller springs according to the EPC should be colour coded blue/brown. The items that Xpart currently supply actually come with a green colour coding instead.
RPD000240 Self leveller damper x 2

The standard Rover dampers and the self levellers (made by Nivomat) have the same ride hieght unloaded, so in theory geometry of suspension not changed. I have not experienced any excessive wear on the rear tyres since fitting self levellers.
It's an easy wheel, and roll bar knuckle joints off job of about an hour per side in my experience. If fitting the self levellers the downside may be that you lose the stiffer suspension handling benefits of the MG by converting to softer Rover dampers & springs.
You may also need to consider that you may upset the balance of the car by having the original MG set up stiff front damper and springs, and the Rover softer set up at thge rear.
I can recommend the self levellers (nivomats), I have had them on all my cars in the past. They remove the up and down pitching movement that often occurs when going over bumps in the road at speed, and stop the base of the towbar grounding on the road.

Hampton Caught
21st August 2007, 08:38
Thanks for the replies, chaps.

As I understand it, I can replace the dampers with Nivomat-made units which were available on the Rover (but not the MG) and that the standard, facelift-model springs may not 'balance' with the new dampers.

Wouod I be right in thinking there was no difference in springs between the facelifted Rover and MG specifications? If not, how much difference in firmness was there and am I (and more importantly, my passengers) likely to feel the rear of the car being under-damped because of the new units?

Also, I presume the change in dampers only would not change the ride height as this is set more by the springs. :shrug:

Finally, John (and others), what is the ball park price for a pair of new Nivomat dampers?

Thanks again,

Steve

Lovel
21st August 2007, 12:51
Thanks for the replies, chaps.

As I understand it, I can replace the dampers with Nivomat-made units which were available on the Rover (but not the MG) and that the standard, facelift-model springs may not 'balance' with the new dampers.

Wouod I be right in thinking there was no difference in springs between the facelifted Rover and MG specifications? If not, how much difference in firmness was there and am I (and more importantly, my passengers) likely to feel the rear of the car being under-damped because of the new units?

Also, I presume the change in dampers only would not change the ride height as this is set more by the springs. :shrug:

Finally, John (and others), what is the ball park price for a pair of new Nivomat dampers?

Thanks again,

Steve

You need to change both spring and self leveller together. If you retain your original spring you will find that the car will sit higher by an inch or two at the back and look weird. The self leveller has a precharge of N2 acting like a spring, this means that that the spring for the self leveller can be of a lower rating(softer) than a conventional spring damper set up.
The self leveller springs are approx £55 incl vat (each) from Xpart.
The pair of self levellers I purchased via ebay for £180.
Not sure if they are available via Xpart anymore. £254.00 each last time I looked.
There used to be a regular seller on ebay who sold them, however I have not seen them come up for some time now. It was one of the good Rover breakers names that seem to come up on here now and again.

rover
21st August 2007, 13:49
As the MG/75 Noseweight max is 100 Kg;the highest of any standard car,I would suggest you check your Noseweight when fully loaded before making any modifications.
The usual reason for the 75 not riding well when towing is not enough weight on the Towbar, not too much.

mattthetourer
21st August 2007, 15:37
I would tend to agree with Rover.One of the reasons I bought the car was to tow and it does that brilliantly with a standard Witter bar.May be down to the balance of the outfit.May I ask what you are towing.Also could it not be possible that the original set up is showing signs of wear?

Hampton Caught
21st August 2007, 16:23
Thanks for the comments, guys.

Rover, I'm very happy with the ride of the ZT-T whilst towing, it's just that it sits so low at the rear. The noseweight (according to my gauge) was a little over 100Kg (given that it's a cheap and cheerful jobbie from the camping shop, rather than a fully calibrated precision instrument, I wasn't too worried!). I didn't have a problem with insufficient noseweight. :lol:

Matt, I tow an Abbey Expression 500L which is a five berth caravan which is within the car's towing limits, even fully loaded, but it is towards the upper limit for the vehicle.

My car is less than 2.5 years old and has covered 15,500 miles, still feels taught and not worn out. I'm sure the problem is because I was pushing the car to it's extreme, given my comments about the caravan, the four bikes (inc 2 kids bikes), ourselves and luggage, the car had a lot of load to cope with.

I'm beginning to swing towards the low-tech route and may get some spring assisters first, as I love the way the car rides and handles and don't want to ruin the balance of the car by having an MG set up at the front with a Rover one at the rear..... and it looks like it could cost a fair bit too, by the looks of it.

Any further thoughts, gang?

Steve

Dave Goody
21st August 2007, 20:49
Thanks for the comments, guys.

Rover, I'm very happy with the ride of the ZT-T whilst towing, it's just that it sits so low at the rear. The noseweight (according to my gauge) was a little over 100Kg (given that it's a cheap and cheerful jobbie from the camping shop, rather than a fully calibrated precision instrument, I wasn't too worried!). I didn't have a problem with insufficient noseweight. :lol:

Matt, I tow an Abbey Expression 500L which is a five berth caravan which is within the car's towing limits, even fully loaded, but it is towards the upper limit for the vehicle.

My car is less than 2.5 years old and has covered 15,500 miles, still feels taught and not worn out. I'm sure the problem is because I was pushing the car to it's extreme, given my comments about the caravan, the four bikes (inc 2 kids bikes), ourselves and luggage, the car had a lot of load to cope with.

I'm beginning to swing towards the low-tech route and may get some spring assisters first, as I love the way the car rides and handles and don't want to ruin the balance of the car by having an MG set up at the front with a Rover one at the rear..... and it looks like it could cost a fair bit too, by the looks of it.

Any further thoughts, gang?

Steve
As a long term caravanner I would suggest putting a bit more weight at the back of the van? Noseweight is entirely dependant on loading? Dave

tigerchubs
22nd August 2007, 12:07
I used the rubber coils for a few years on a Volvo 940 with no issues, They took minutes to install and removed them out of the towing season. I Didn't feel the need with the 75 though. I also tow a 5 berth Abbey but kept the weight in the car to just the Awning and lighter objects. I set the draw bar weight at approx 70kgs and she towed like a dream.

oakridge
22nd August 2007, 12:35
As a long term caravanner I would suggest putting a bit more weight at the back of the van? Noseweight is entirely dependant on loading? Dave

Not too far back though as it can induce snaking; there does seem to be a lot of caravans on the road nowadays where the jockey wheel is almost on the ground. Weight distribution is the thing.

After caravanning for many years we transferred to Land Rover and Livestock trailers, now that is much more fun. Now you get 3 sows who decide to have a row in the trailer of all sleep in a pile at the back, well, that is exciting.

Malcolm

Hampton Caught
22nd August 2007, 12:56
Now you get 3 sows who decide to have a row in the trailer of all sleep in a pile at the back, well, that is exciting.

Malcolm

Sounds like my kids bouncing around in the caravan on the motorway. :getmecoat:

For the sake of clarity, I would hasten to confirm that the above comment was by way of a quick gag and not in fact anything to do with my practices whilst taking the family on holiday. I wouldn't let the kids loose in a moving caravan anyway. Far better to get them to put their cycle helmets on and sit on their bikes on the roof of the car. :getmecoat: again!

Thanks for your comments on the spring assisters, Tigerchubs. I'll give the Grayston ones a go and support a local business at the same time :D . I'll have to wait until next Spring before reporting back on their effectiveness, though.

As an aside, I always remove the jockey wheel whilst in transit, to improve the ground clearance and reduce the nose weight a bit. I lock the caravan to the tow ball too, so should I park and leave the caravan, it's going to be really difficult for anyone to unhitch and steal the 'van. I always remove the jockey wheel in storage too for the same reason.

Thanks again for your comments,

Cheers, Steve

Dave Goody
22nd August 2007, 18:21
Not too far back though as it can induce snaking; there does seem to be a lot of caravans on the road nowadays where the jockey wheel is almost on the ground. Weight distribution is the thing.

After caravanning for many years we transferred to Land Rover and Livestock trailers, now that is much more fun. Now you get 3 sows who decide to have a row in the trailer of all sleep in a pile at the back, well, that is exciting.

Malcolm

With many caravans the design fault is in the storage/ gas compartment being at the front. 2 gas cylinders and loads of other heavy stuff in here and getting sensible noseweight very difficult. Try to balance it with other heavy stuff further back. I used to have an Eldis Crown, very streamlined and stable towed with a sierra xr4x4 I decided one dark night to see how fast I could go before it started to twitch [ cant say how fast, but it didnt ] Dave