Range Rover P38 – Air Suspension Restoration And Front Brake Renewal

Outdoor workshop
Range Rover Brakes And Suspension Maintenance

Trials and tribulations of working on a Range Rover P38A in Botswana.  This particular post covering the conversion from coil springs to air, and fitment of new front brake disks and calipers.

Anybody looking for detailed, illustrated guides to working on Range Rover P38 suspension and brakes should load the pages linked immediately below, this is merely my tale of intermittent woe and final sense of achievement.

For brake maintenance I recommend this page on RangeRovers.net.

For the suspension replacement I followed this guide – except I had the pleasure of removing coil springs with spring compressors first. Be careful.

Air Suspension Failure

Way back in October 2012 I pulled into my parking spot at Toteng after another 570km journey up from Francistown, and as I dropped the suspension to “Access” level there was a loud phush and the car dropped onto the bump-stops.

My mechanic (an ex-Land Rover workshop manager)  point-blank refused to repair the air suspension on the grounds that it would do nothing but give me trouble, not having the time to do anything about it myself I had no choice but to accept a coil spring conversion (US$800), new Bearmach shocks ($430) and 4hrs (only?) of labour ($110).

The ride on coils was not bad, and the increased ride height did at least solve the problem of the slightly oversize tyres rubbing the front wheel arches at full lock.  I was less than impressed that one of the Bearmach shocks blew out after less than a year, leading to a somewhat bouncy ride over uneven surfaces.

Then we did a couple of trips with the camping trailer, and the problem of non-self-levelling suspension became evident as the back-end sagged quite badly. There was a choice: fit stiffer coil springs and suffer a harder unladen ride or go back to air.

In the interim I had done a bit of a post-mortem on the air suspension and some research: soon after the suspension failure I had to get a leaking exhaust fixed.  The leak was at one of the joints just under the rear cross-member.  Coincidentally right underneath the main airline from compressor to reservoir tank.  The exhaust had been leaking hot gas while I was driving but when I stopped there was no longer any cooling from the 120km/hr airflow, the airline melted and all the air escaped.  Cost of a new airhose and couple of couplings would have been $10… (although the OEM airbags were also at the end of their life).

A set of Arnott Gen III air springs was ordered directly from the USA, and sundry parts like air hose and couplings procured from the ever-helpful Andy at P38Spares.

Shocks were ordered from Motovac, the units supplied were labelled as Monroe Reflex D8644 (front) and D8645 (rear).  At the time of writing they’ve done a couple of thousand kilometres and feel fine, not really tested offroad yet though.

Brake Failure

Moving on to late-2014 and there came a terrible grinding noise from the front brakes.  One of the pads had worn down to the backing material in a very short time and in the final moments of its life scored the brake disk as well.  Being in Orapa none of the local motor spares shops had the right pads so I had a set sent over from Francistown to keep me going, at which point a “warped” disk was also revealed through a most unpleasant vibration while braking (much discussion on t’internet about disk “warping,” which seems to conclude that the effect is actually due to differing friction levels caused by heat treatment and or deposition of pad material when the parts get overheated).

While replacing the pads I also identified the root cause of the problem: the slider pins on the pad carrier assembly had seized up so every time I braked it was pulling the pad tighter against the disk, rather than floating when the pressure was released.

New pads, disks and shock absorbers (dampers, for the pedantic) were ordered from Motovac.  A somewhat painful process as the first pair of disks was the wrong size – parts look up failure as they were for something else in the Land Rover stable – and the replacements took forever to arrive due to the delivery truck being hijacked so it was a case of third time lucky.

The Works

2014 Christmas holidays arrived and I set to work, hoping to have a functioning car in the not too distant future.

After a considerable amount of swearing I had managed to remove the front springs, bending the first set of coil spring compressors (Motovac) into unusable pieces of metal, and taken a trip to town to buy a second set (Wheels – the map is wrong, they are at the north end of Blue Jacket Street).

Following the guide for air spring installation I fitted the new springs with relatively few issues.  The hardest part at the front was to get the circlips in place: much levering with screwdrivers and contorted handwork through the shock turrets (I managed to do the job without removing the wheel arch liners).  At the back I was troubled by the air inlet on the shock being quite low down and almost obstructed by the chassis, however I did manage to get the air hose seated without leaks.

Various guides talk about having to reset error codes on the vehicle computer but all I did was replace the compressor fuse (removed when coils were fitted) and everything behaved itself.

While removing the coil springs I had tried to fit the new brake disks, unfortunately it seems like I was supplied with Range Rover Classic Or Discovery 1 disks, rather than P38/Discovery 2.  I also delivered the old calipers and new seal kit to a local “specialist” to recondition.

The calipers came back with a nice leak from one of the cylinder seals, destroying my faith in local abilities (and not doing any favours for the paint on the wheels) so organised a new set from P38Spares, another slight problem that the observant might identify in the picture below.  Resolved by buying another one and having it shipped out (great, another 3 week delay…).  Unfortunately postage to return the surplus unit costs the same as a new one so there’s no incentive to do so.

P38 new front brake calipers. Small problem.
P38 new front brake calipers. you may notice a small problem.

Eventually the brakes were done, enlisting the help of child labour to press the pedal for bleeding, not as traumatic an experience as I was expecting.

In Conclusion

So, at the end of the day a satisfied glow as I have a car that goes up and down when I want it, and stops when required – and all with my own fair (now slightly scarred) hands.  It’s done a few thousand kilometres including a trip to Gaborone and back, a few weeks of city life, and some local duties around Francistown without issues arising from my mechanicing.

Unfortunately it’s still a 13 year old Land Rover product and has now developed a coolant leak that has led to a couple of instances of overheating and having to refill the cooling system… I have been momentarily attracted by Toyota Surfs and Mitsubishi Delicas, but think I will try and sort out the Range first: better the devil you know.  And that V8 isn’t so expensive with fuel prices as they are now…

Range Rover on the Makgadikgadi
Range Rover on the Makgadikgadi – it’s bottom shouldn’t sag so much now.

Author: Michael

Parent, husband and civil engineer born and raised in Britain before emigrating to Botswana. Interests in construction, information technology, fitness, mechanics and mapping, among others.

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