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Richard's TGB13 6x6 Command Cab

My experience/latest stories Driving Off road Mechanical stuff Engine work Interior self recovery Plans Transfer box tyres/gearing

I've got one of these bad boys and it is great. It has 7 seats, 2m (6'6") of boot space as well as all the usual TGB advantages. I've started upgrading and sorting it out and this page is dedicated to the process of learning what, why and how.

Why 6x6 rather than the 4x4?
The 4x4 is great but aesthetically the 6x6 looks better. In addition it is just ludicrous, I love the attention it gets as I drive around town and with 7 seats I can take my kids, and several friends, the dog, fridge, food and all my off road gear with room to spare. The ride is smoother less bouncy or choppy compared to the 4x4 and the off road manners are just as good. I have to live with negligible acceleration and bugger all top speed.

My experience so far

Out of the 4 or 5 off roaders I've owned in the last 6 years this is probably the most interesting and practical. From a driver's perspective it is comfortable ( especially with Recaro's fitted) and remarkably civilised to drive. It is far less 'choppy' than the 4x4 mainly because of the extra length and weight and is a little quieter although you do get quite a whine form the straight cut gears in the hubs and rear axle PTO. The steering is heavy but once on the move it's OK although you have to steer like crazy because the gearing in the steering box is very low to compensate for the weight of the truck and lack of power steering. The cab gets rather warm even in the cooler weather we get in Scotland and during the summer I had to have all the widows open all the time but still sweltered. I tend to leave the safari front window open most times with a bit of wood pushed into the frame just to keep the pressure off the window catches. As the winter approaches, I find that the heating is quite efficient, although the side windows do take some time to demist. I've removed the 2 partitions so the air can circulate just that much better. It is rather pleasant to have all that warmth coming through the bulkhead.

I've fitted a Starcom1 intercom with pit crew headsets so we can all talk to each other on the move and during the summer one of my passengers came over all "Kelly's Heroes" and did a Sgt Oddball out the machine gun hatch and sent me into every boggy patch he could see from 15 feet up! The purchase of an Engel fridge has also been a tremendous addition so we have cool drinks and fresh snacks that have not been flung around whilst offroading. The rack I've built to hold some of my gear has also been welcome and has stopped everything being flung around so much.

I've had a leakage problem ever since I got the truck and I've spent ages sealing up every seam I could find but to no avail. So over the New year I took the truck into my works warehouse and firstly removed the rearmost top section, clean up the edges and stuck it back together again. Then I noticed that the roof is made up of 3 sections (top plate, outside corner and inside corner) with sealant keep the wetness out. I re-covered it in tiger seal Pu sealant which can be over-painted and lo and behold it's dry. Now it's time to put in new internal panelling and insulation. The seal at the cab/load area join was OK and I couldn't be bothered to split it in any case!

Driving Off Road
Amazing! I've had a few people refuse to let me join them because they didn't want to have to wait around and drag me out the mud every few feet, but I had the last laugh by being able to drive through almost everything. I am able to push through the deepest mud and ruts and sit on the other side to drag them through but I have found that it tends to dig into banks of earth rather than climb over and I have been stuck on the flat when the 2 rear axles have fed mush to each other. So long as you keep moving you are likely to be fine. Tyre choice is critical, however, and I was advised to get shot of the Trelleborg tyres asap. I now have Fedima Sirocco extreme off road tyres that have a very aggressive pattern and these have made a huge difference. When driving off road you have to take the time to learn what works best for your vehicle and the terrain you drive in and the Volvo is no exception. The difflocks are great and make a massive difference but as with any difflock you need to watch out for side slopes (leave them off) and poor steering with the front axle locked.

I've found that the portal axles give an advantage most people do not at first realise. Obviously with so much clearance you tend not to get stuck in ruts and with 6 wheels and 12" wide tyres the ground pressure is very low so you sink in less, however it is when the axles articulate that you gain a massive advantage. Normally, when driving in ruts, the axles rotate around the midpoint of the truck as they articulate. This can cause the axle tube to touch the ruts and you get stuck. With the portal this seldom happens as the axle tubes are so high up. The downside is, however, that when you do get stuck you get VERY stuck!

Mechanical work
So far it has been an easy truck to work on with very little going wrong. The biggest job so far was fitting the Kenlowe fan which would have been easier had I not broken the radiator. Fine tuning the thermostatic control took some time with the setting to be much lower (i.e. switching on at a lower temperature) than normal to cope with off road conditions where the truck is sat still with little airflow over the radiator and further compromise by the winch and other stuff. Over time I have realised that the standard 2" radiator was not enough so I have now fitted the deeper 3" one from the commercial C303. These are relatively rare and usually need to be re-cored at a cost of £200 but are an almost straight replacement with only the support bar at the bottom needing to be extended as the 3" rad is a bit longer. The improvement in cooling is immediately noticeable with the fan working less and the engine running cooler which is important now I'm running LPG.

I had a funny one - the horn kept on sounding as I went round corners! The problem turned out to be a loose wire inside the steering column but boy was it tricky to find. 24 volt has been quite easy to get used to with only a few bit being fitted that were 12v and therefore blew up rather quickly.

Engine work - not only lpg
Once I'd fitted the LPG I knew that one day the valve seats would get burnt out and need replacing with unleaded ready ones. Over the first few thousand miles the performance go steadily worse and no amount of tappet adjustment seemed to work so I got a spare head rebuilt with unleaded friendly (hardened) exhaust seats and with increased compression to make use of the extra octane of the LPG. When first done (i.e. in the first few miles) it was great but immediately there was a horrible pinking problem followed by an increasingly bad death rattle from the engine. Long story short the cam had worn badly, 'dishing' 4 of the cam followers so sometimes the valves weren't opening properly and other times they weren't closing. The also meant that the small end (gudgeon pin) had become worn resulting in the pistons not moving properly. Basically the physical integrity of the engine had become compromised!

I sourced a replacement engine from Sweden, one that had done only 20,000kms rather than paying £3,000 for a rebuilt higher performance one and had it fitted. There has been a huge difference meaning the engine starts, stops and runs perfectly and has huge amounts of torque for off road but is still dog slow on road. This is caused by the over-size tyres increasing the gearing too much and the search is on for inexpensive 35" tall tyres.

Tyres and Gearing issues
I fitted Fedima Sirroco remould tyres in July 2005 but after sorting everything else out I clearly had a gearing issue running such oversize rubber. In Jan 2007 I had the chance to go back to standard tyres and the difference in driveability and ease of cruising was amazing. Standard tyres are about 34" tall whilst the Fedimas are about 37" making the truck 7.5% overgeared. After loads of research I found that the only reasonably priced tyre that would fit was the Simex Jungle Trekker at 34.8" tall but tougher and better on road than the Extreme Trekker that the Fedima is based on.

The only problem now is that the rumbling noise that has always been there is now at its worst at 50mph (ie cruising speed)!

Transfer box problems
So onto the next thing to go wrong. The truck had always been noisy at highway speeds but it had been getting so bad that even with the headset on the rumbling and vibration was exhausting us. So after some diagnostic driving and fixing the king pin bearings, fitting new shock absorbers/dampers I figured out it was the transfer box. The noise disappears in low ratio and is much less in high ratio 6 wheel drive so a spare box is to be fitted very soon.

Sorting the inside
The TGBs are, by all accounts much more refined than the Pinzgauer and certainly more civilised than the Landrover 101 but as with all Forward Control vehicles they have their idiosyncrasies. The layout is a little odd with very little foot room and the switches being just a little too far away for comfort. The seats are good but after 30 years they are knackered and generally ripped and sagging. The central consol/engine hatch has seen better days and there is a load of noise coming from various gaps in the soundproofing. Interestingly there is a lot of very useful space behind the seats and plenty of flat bulk head to fix bits and pieces to. They are, however, noisy, with road noise from the tyres (aggressive off road pattern) and from the straight cut gears in the hubs, PTO and gear boxes and on long journeys this is a real issue. Being a biker, I have loads of earplugs and even some custom moulded ones with headphones built in so I can listen to my MP3 player but this is rather unsociable with passengers, not that you can talk to them much especially if they are in the back.

So, what can be done to set up the interior to suit a family type off road truck. Well, first thing is to address comfort and noise then to move onto the gadgets we all seem to need. The thing borne in mind at every point was not to over develop the truck beyond its value which has fallen by the wayside somewhat.

1. Seats: I ripped out the original ones out in favour of a pair of Recaros bought from ebay for £41. Once welded directly onto the original rails they have proven to be an ideal replacement and very comfy on long runs, the first being 400 miles! The rear bench seat is fine and now the LPG tank is behind it and the winch batteries are underneath I don't move it much. The back get put down when I'm working or sleeping in the back. All the C303s came with stretcher hanging straps which are just right as camp beds. As a medical supplier I have ready supply of cheap stretchers!

2. Noise: Easy stuff first. I replaced all the soundproofing felt in the cab area with new material and put down rubber matting in the cargo bay and the rear passenger floor then realised that I still could not easily chat with rear passengers and was worried about damaging my 7 year old daughters hearing on long runs so I fitted a bike intercom with F1 pit crew style headphones with the extension sockets fitted into the difflock control panel and above the rear doors connecting ourselves up is easy without trailing wires everywhere.. Magic! Now we can chat on the slow journeys to and from events no matter where in the truck passengers sit and with the stereo controlling the music (including the ipod) integrated into the system the noise issue is no longer a biggie. The CB is left out as it is too difficult to balance the volume but once in the mud the headphones come off and the CB is fine. I've had a few passengers imitating Donald Sutherland (Kelly's Heroes) out the machine gun hatch, giving me directions and with the intercom we can all talk perfectly. Great fun! The stereo speakers are mounted in the rear compartment and are adequate, sort of.

3. Stereo & CB: I bought a relatively cheap CD/tuner with an aux socket to plug in the ipod and made a roof mounted pod wit my new plasma cutter with enough space beside it to mount the CB. It was the only place for it go really and despite worrying about clouting my head off it each time I got in and out it has worked out just fine. It looks good even if it's not exactly American Hotrod standard.

4. GPS: I have a Garmin 2610 which fits in my car and on my bike and has the great advantage of being waterproof. I bought an extra car mount and stuck it on and hey presto I'm ready to roll. The Garmin GPSs run on 12v and 24v so power is no problem.

5. Storage: Everyone who heads out into the Wilds needs Stuff. I have the usual self recovery gear (High Lift jack, bridging ladders, KERR, extension ropes ground anchor) as well as spares, tools, fuel and water, camp seats, fridge. The spare tyre can no longer fit on the back door so it went in the back until LPG came along. Now it lives in my back garden!. End result was a mixed up mess of kit within 30 seconds of hitting the trail so I built a rack for the big stuff and jammed the fridge and boxes together to hold them in place. It's all level with the wheel arches and covered so I can sleep on the top when off camping. After a few months of I realised that the Fridge is better in the middle in front of the rear seats and the ammunition boxes holding the rest of the stuff strapped down in the back.
There is a safety issue as well, after all a lump of steel flying down from the back door would hurt if it hit you in the head! So everything must be squared away.

6. Self recovery: As an experienced a reasonably committed off road driver, I have collected a reasonable amount of equipment and the experience to know when to use it. The odd thing is that with the 6x6 you tend to need each one a little more often than you would think is strictly necessary for such a capable truck. My Blitz 4x4 had all the toys: winch, bridging ladders, ground anchor, KERR (bungee), snatch (pulley) block etc, but apart from the winch and occasionally the bungee the rest were hardly used. Last Sunday I used every bit of equipment with the 6x6!

Winch: I have fitted a 12,000 lbs (5500 kg) winch with plasma rope rather than wire on a custom winch mount. Whilst not helping the angles it has meant I have been able to self recover as well assisting others, however when I get stuck now, I get REALLY stuck and the whilst the winch is strong enough I rarely have a sufficiently strong anchor point so I generally have to use the pulley block as well. I also sell Pull Pal ground anchors and have a 14,000 lbs version that is my profit from selling another 10!
Winch Mount: I wanted a removable system but this proved to be impractical so I had a local fabricator run me up a little something that has been tested beyond all reasonable doubt by being rammed into trees, rocks and earth banks and come up scuffed but otherwise perfect. It fits over the existing bumper which is easily strong enough wit only the loss of the recovery point in the middle going against it. I fitted 2 'D' rings to the chassis legs at the front to act as recovery points which I bridle for safety reasons.
Powering the winch: The C3's are supplied with a puny 35A (24V) alternator which is enough to power the truck and the normal toys but certainly not enough for a winch which can draw up to 210A! The answer is, ideally, to fit a HUGE alternator (~200A) but that introduces a number of problems. When pulling that kind of power the alternator will slip drive belts and put a large strain on the engine as well as being very expensive and hard to fit. The 2nd option is to fit a decent size of alternator (70A from a radio truck) that is a direct swap and fit 2 sets of HUGE batteries. Answer is option 2. Two sets of 90Ah batteries connected directly in parallel will give 180Ah of winching with an extra 40A available from the alternator. Option 2 is the way to go so long as you keep the starter batteries and fit a split charging system.
Bridging ladders: These are plastic/fibre waffle boards that are used to reduce the angle of a ledge or set into the mud to increase the grip. I have found that sometimes all the rear axles need is a tiny amount of extra lift or grip and away it goes. They are now kept very handy.
KERR: or Kinetic Energy Recovery Rope. This can be useful for recovering Landrovers or Suzukis but it is bugger-all use for being recovered simply because of the size of the Volvo.

7. Camping: Once I realised that stretchers are not orange camp beds with handles, I made a series of 4 steel 'joists' that hook onto the sides of the tub behind the rear seats and carry a 2 halves of a plywood floor that takes 2 inflatable camp beds and allows comfort and convenience. It takes under 5 minutes to refit the back.

What are my plans?
Initially get the truck running well, sort the oil leaks, rust and holes and fit some sound deadening matting and panelling to the inside. After that is done I'll get busy with the toys. I'm not going to spend silly money on non-removable stuff like engines changes because I do believe in keeping expenditure to within the limits of the value of the vehicle i.e. spending £5,000 on a diesel engine upgrade when the car is only worth £4,000 is a bit daft.

Things that have been sorted

difflocks fixed

engine serviced - twice! use 20W/50 oil for the UK it runs a lot better. Lucas Oil improver being sworn by!

engine replaced!

Leak in roof fixed

painted - then repainted in semi gloss to make it waterproof. D'oh

Starter motor replaced

Carbs refurbished

Inlet/exhaust manifold gasket replaced

permanent fixing for the fridge

Roof lining and sound proofing for the rear - to be removed and replaced - more soon

rust repaired

new transfer box

Thing I want to sort

Comfy rear seats

snorkel air intake

MORE POWER

Things that have been done PHOTOS (not fully done yet)

Recaro seats from a Golf GTI

reversing camera and TFT screen fitted

11.5 x 36" Fedima Sirocco tyres - similar pattern to Simex Extreme Trekkers

Kenlowe 16" blower fan to replace prop driven radiator fan

3" radiator fitted - very cool

Starcom1 pit crew style intercom system

Acoustic matting in cab - and rear load area

12,000 lbs winch and custom winch mount with dash mounted remote control panel and 130' plasma winch rope

CB radio

Car style radio/CD player

Recovery points at front

12v circuit using a step down transformer

fitted an old wheel to the back door as a rack for ropes and stuff whilst off road

racking set up for load area to stop my kit from flying around

Interior lighting (5 x 16W fluorescents = 60W each!) - very bright

2 Extra winch battery banks. I have 225 Amp hours of battery life!

Split charging system from X-eng - has been removed as it was useless for my needs!

55A Bosch alternator

Wiper blade mounted washers

300W 24vac inverter

LPG fitted - full story

132ignition distributor fitted

Things that are on order/to be fitted

Unleaded petrol converted head with 2mm skim for extra power - since removed as engine was replaced

Wish list

Disc brakes - unlikely at £700 per axle but a man can dream

rear winch - got the winch just nowhere to fit it!

Full on camper job

big lottery win

Wife to magically return to 25 years old and look like Kylie

Me to become 25 again

Kids to behave themselves