Volvo Portal Axles Under My HZJ78 Troopy (2 Viewers)

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This project was put on hold for a while, after I received the axles from the UK.

A couple of weeks after the crate arrived, I found some time to open it up and have a look at my new Volvo portal axles.

I was devastated to find that they did not have the right hand rear diff centre offset, from a 4x4 Volvo C303, that I had been promised, but that they were the more centred rear diff centre housing from a rear axle on a 6x6 Volvo C304/C306.

I contacted the seller, and the f**kwit refused to accept that he had sent the incorrect axles, kept saying that he knows more about these axles than I do, that I am never happy, and that he had sent exactly what he had originally agreed to. He eventually just started to ignore my demands that he do something to remedy the situation at his cost.

I then also worked out that not only were they not the right hand rear diff centre offset, but as I suspected from the incorrect rear offset, that they were also not the 5.99:1 ratio diffs that I had been promised as well, and were actually 7.10:1 ratio front/rear diffs.

After spending so much for the axles, and so much in freight, import taxes and duties, etc. to get them here, about $9000 all up, I had recevied axles that were not what he promised I was buying, that I didn't want, that I couldn't really use for my conversion...it was very depressing.

Thankfully, the guy that runs the 4WD team that the seller is (was?) a part of, decided to take it upon himself to remedy the situation, when he really didn't have to, as it was sort of indirectly related to his team. He called in some favours from people he knows in Europe, and has got together a replacement rear axle housing, with the correct right hand diff centre offset, a pair of matching rear axle half shafts, and a pair of front/rear crownwheels and pinions in the correct 5.99:1 ratios.

So, I will have to pay to have these replacement parts shipped out from the UK to Australia, as the original seller refuses to accept any responsibility for his possibly intentional, or less likely accidental, f**kup. But at least I will have what I originally thought I was buying, and what I need for the conversion to work.

I am now waiting to get the replacement parts shipped from the UK, so hopefully in a couple of months I should be back on track with the correct axles that I should have received back in August last year. And it will be over a year after I paid for them back in February last year. I f**king hate the seller, I hope he dies a slow and painful death.

These are the incorrect axles that I received...
_MG_3519b.jpg


This shows the approximate difference in diff offsets of the 4x4 and 6x6 Volvo axles compared to my standard HZJ78 axles. The red lines are the centre line of the axles, the centreline of the diff centres, and the outer red lines show the maximum track width I can go to at 50mm over standard (hopefully with recent updates to the rego rules, this 50mm maximum increase will no longer apply, and I can use the standard Volvo axle track width). The outer black lines are the track width, plus the second black line on the HZJ78 axles show the track width plus 50mm maximum increase...
PortalDimensions2.jpg


This is the offset of the incorrect rear axle, showing approx 19 inches from the right hand side portal box flange to the edge of the diff centre cover...
_MG_3541c.jpg


This is the offset of the replacement/correct rear axle, showing approx 14 inches from the right hand side portal box flange to the edge of the diff centre cover, hopefully he is debracketting and cleaning these up for me before he sends them...
IMG00065-20101027-1946.jpg


This is the diff ratio plate on the incorrect axles, showing the incorrect 9X31 ratio (= 3.444444 x 2.06 reduction in the portal boxes = 7.095555:1), that the seller carefully painted around when refurbishing the axles, so he should have (or did) know they were not the correct ratio...
_MG_3528c.jpg


This is the diff ratio plate on the replacement/correct axles, showing the correct 11x32 ratio (= 2.90909 x 2.06 reduction in the portal boxes = 5.992727:1), that I should have originally received...
IMG00066-20101027-1947.jpg
 
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Hello SimonInAustralia,

In Canada we didn't get blessed with Toyota bringing in Troopys. Ever. So pardon the ignorance: what modifications did you have to carry out in order to fit the Volvo portal axles to your camper? How much more clearance did they provide, and how did they affect the ride, assuming they made a difference? What can you tell me about the advantages and disadvantages of those axles? Are they solid, reliable units that will take a beating and come back begging for more?

Any info you can throw at me would be appreciated. Thank you!

Cheers, Mk61+
This is an ongoing build, not completed, only really has started with trying to source the correct axles, as per the post above.

A list of planned modifications to fit the axles are in the first post of this thread.

They should provide approximately 4.5 inches of additional clearance both under the axles/diffs, and above the tyres/under the guards.

They shouldn't affect the ride, as the plan is to mount them using the standard Troopy suspension, by putting the appropriate brackets/coil hats/etc. onto the axles. The axles are a little wider than the standard axles, which might help offset the increased centre of gravity.

Hopefully they will be tough enough for a touring oriented truck, as mine is. They are used in lighter comp trucks and the UK and Europe, lots of Land Rovers for example, and are said to handle them well, but with the extra weight of my troopy that might not handle the same sort of abuse, which I don't think I will be giving it.

Unimog axles would be a lot tougher, but also a lot heavier, not as easy to get a 'fast' ratio for, and a lot more hassle to get fitted to my Troopy.

If you have anymore questions, feel free to ask, I'll try to answer them.
 
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Have spoken to an engineer, he likes the idea and is seeing if we can get around the registration department maximum allowed 50mm increase in wheel track, as the Volvo axles have a wheel track that is 105mm wider than the standard HZJ78 axle for the front and 120mm wider for the rear, but he thinks it is a good idea as it will make it safer with the wider track to counteract the 4.5 inches that the portals lift the axles/diff centre/truck.

Standard HZJ78 Front Axle Wheel Track: 1435mm
Standard HZJ78 Rear Axle Wheel Track: 1420mm

Volvo Portal Axle Wheel Track: 1540mm

Increase in Front Wheel Track Over Standard: 105mm
Increase in Rear Wheel Track Over Standard: 120mm

If I can't get it engineered with the standard Volvo axle wheel track, I might consider having the Volvo axle wheel track shortened, if that is even possible.

Or it might be possible that a disc brake conversion will result in a narrower track, I have read that some ways of doing it does reduce the track, but others have told me it increases the track.

Required Reduction in Front Wheel Track for Registration: 55mm (27.5mm per side)
Required Reduction in Rear Wheel Track for Registration: 70mm (35mm per side)
I did hear back from the engineer.

He spoke to the head of the rego department testing station, who spoke to others higher up in the rego department, and they said that I had to adhere to the maximum 50mm increase in wheel track over standard for the vehicle.

That was going to be a real pain in the arse. Was going to have to have the axle housing made narrower on one side, and have custom/shorter axle half shafts made to suit the narrowing on that side.

Thankfully, it looks like this might no longer be necessary.

A new revision to the National Code of Practice for Light Vehicle Modifications, which our rego department uses for their rules on allowed modifications, was just released at the beginning of January, 2011.

This update to the NCOP has changed it to include the second paragraph in this rule...

4.2.11 Off-Road and Goods Vehicle Wheel Track

The wheel track of off-road four wheel drive vehicles and goods vehicles (MC, NA, NB ADR category) must not be increased by more than 50mm beyond the maximum specified by the vehicle manufacturer for the particular model.

If a solid axle from another manufacturer is used, the wheel track may be increased by 50mm beyond the maximum specified by the vehicle manufacturer for that particular axle, provided all other requirements such as clearances and the tyres do not protruding outside of the vehicle bodywork.

So, I have to get my engineer to clarify this with the rego department, to see whether this change in the rule applies to my truck, but hopefully it will avoid a lot of hassle.
 
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portalaxles#2

Hello SimonInAustralia,
I appreciate your not wishing to get in the way of Wayne's Troopy build thread. Such protocol online never occurred to me as i am not in the habit of reading them, let alone participating. Thanks for the heads up.
I am wondering about portal axles, and have been for a long time, as i am aiming for as tough and practical a vehicle as i can get; for me, my car isn't simply a transportation device, it is also a home (at least while on trips, which i want to be two years long), as well as a tool (for example, the factory PTO's splined output shaft could be used as a drive for, well, i think that's limited by one's imagination-a water pump? a genset? Am i silly? Perhaps, but the practical possibility is there). You read my mind as if my skull was transparent when you mentioned Unimog axles, so thanks for saving me the trouble of asking; i'd have a 1980 (approx.) double-cab Unimog if i could afford it, but the Troopy will do; as a plus, the Troopy will do decent duty as an in town grocery-getter if the need arises. Which it will, as i do eat, and many of my friends and rellies live in big cities like Toronto and Calgary.
I am currently having my Troopy significantly modified (actually it's the one Wayne is doing), and if i ever get portal axles, it won't be for a dog's age, if ever, but any info is useful. It's fantastic that the increased height will be at least partly made up for by the axles' increased width. When you carry out the conversion of your Troopy to the portal axles, i hope you post it.
Thanks for taking the time.

Cheers, 61Mk+
 
No problem at all.

I will keep this thread updated as the portal conversion progresses, but it is not going to happen quickly. I have to save possibly approx. $8000 to pay someone to do the conversion, and always get sidetracked into spending my money on other things, such as a Warn twin motor high mount winch build up at the moment.

I did consider a hydraulic pump attached to the PTO output, to drive a hydraulic pump, and thereby a hydraulic winch. But I decided against that, as it seemed that the truck could not be driven to help with the winching in that configuration, as it can with an electric winch. The hydraulic pump could also have been used to drive other tools, such as a hydraulic chainsaw to clear fallen trees off of the tracks.

If I won a lottery, I'd love to buy a Unicat...
UNICAT® | UNICAT GmbH | UNICATAmericas Inc. | Expedition Vehicles
...but it would be a lot larger, and not as practical to use on tighter tracks, or following in the tracks of narrower wheelbase trucks that we have over here.

I noticed this Unimog on Australian ebay the other day...
http://cgi.ebay.com.au/Unimog-404-D...-/220722384999?pt=AU_Cars&hash=item3364145067
...would make an interesting base for a camper, though probably still limited in top end speed for highway cruising by the diff ratios.

Your truck is coming along nicely in Wayne's build thread, the mods are looking great, he doesn't muck around and gets right into it.
 
Next problem is finding a RHD tie rod and steering link set.

My axles didn't come with any, as they were bought from the UK, where they only have LHD tie rod/steering link sets.

Plenty around for LHD in UK/Europe, but can't find any RHD in Malaysia (where they where used in a RHD version by the military.

So, the options seem to be...
- keep searching and hopefully find a 2nd hand RHD set from Malaysia
- ream out the tapered tie rod hole in the cast 'bracket' on the axle portal box, to possibly suit an off the shelf tie rod end, and have a custom tie rod/steering link made up using those off the shelf tie rod ends
- have an adapter machined to fit the tapered tie rod hole in the axle, have a custom tie rod/steering link made up using heim/rose joints

If I can't find a genuine Volvo RHD tie rod/steering link set, I am leaning towards having an adapter machined up to suit the tie rod hole, and using heim/rose joints. I'd rather not modify the hole in the axles.

This is a diagram from the Volvo parts manual, showing a LHD tie rod and steering link...

PartCatalogue20-Steering1.jpg



This is the tapered tie rod hole in the cast 'bracket' on the Volvo portal boxes, where the tie rod fits into. The hole is approx. 17.3mm (11/16") diameter at top end, and 14.7mm (9/16") diameter at the bottom end...

_MG_4013b.jpg


_MG_4014b.jpg


_MG_4017b.jpg



These are aftermarket replacement tie rod/steering link ends and full sets made by FMV4X4, but are only available in LHD...
FMV4X4 Steering Links

mdq1e1dthmSmall.jpg


f8qyfu0mxq7zSmall.jpg


oub4wzpcukaSmall.jpg



This is one end of a custom tie rod, which looks like it might be using a heim/rose joint. You can see a bend in the end of the tie rod which is needed to clear the axle on full lock...

P7170024.jpg
 
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i was encouraged to look at this thread and love what you are doing ...
but
not the reason you are doing it. as one old fart told me years ago:
"sonny" he said "why do you want to go to bigger tires?" :hmm:
"cause" said I, "i don't want to get stuck any more" :D
"sonny, you will still get stuck. you will be just stuck worse" :eek:

similar idea :idea: , once you get them puppies stuck you are going to be ... upset. :mad:

but

I LOVE the build. :bounce::bounce2::bounce: subscribed.

<i do hope you plan on reinforcing the front and rear frame members since you MIGHT need some serious pull to get back out of the hole you just fell into>:hillbilly:
 
Hello SimonInAustralia,
I was going to comment and ask more, however all the other contributors have saved me the trouble. I agree with you on the Unicat beasties, however they really require a large amount of unneeded cash hanging about; i used to hanker for a (approx.) 1980 double cab Unimog, but that is a huge expense to acquire and build up to what one wants. As an all-rounder, the Troopy is reliable, roomy, has parts available worldwide, will do pretty well anything including towing and getting groceries in town, etc. In other words, it can't be beat as far as i can tell. Stick to yours, you're already making the best of it. And best wishes for your mods, which i am happy to follow, thanks.
It's a stinking shame about the UK clown that made your life unnecessarily difficult; the pope should really put a curse on him/her.

Cheers, 61Mk+
 
i was encouraged to look at this thread and love what you are doing ...
but
not the reason you are doing it.

once you get them puppies stuck you are going to be ... upset. :mad:

<i do hope you plan on reinforcing the front and rear frame members since you MIGHT need some serious pull to get back out of the hole you just fell into>:hillbilly:

Yep, that is why I am putting the winch in the rear, to make sure I can pull myself out backwards onto the track I have just come in on, when I get stuck by trying to push it too far.

I am in the process of planning to build up a strong twin motor Warn high mount winch to put in the front, and will then put the existing front Warn low mount winch onto the rear (in much the same way you did with the rear mount PTO in your Troopy build thread), to pull me out backwards when needed. Will probably start buying parts for the high mount winch this week.

Only problem will be when I only just manage to drive in to somewhere through deep snow for a multi-day backcountry snowboarding mission, and it snows heavily again while I'm in there, that might cause some problems in getting back out again, but nothing a good strong winch shouldn't sort out (with a hand winch as backup).

Will most likely be putting 37x12.5 inch tyres on it (38x15.5 is probably overkill), there should be plenty of room for those plus chunky snow chains, at least above the tyre due to the extra 4.5 inches of clearance it will give above the tyre. That theoretically should let me go 9" over standard tyre diameter, so 41", but don't plan to go that big, 37's should do to begin with. Might need some extra room at the front and rear of the wheel arches though, will have to see once the 37's are on, and flex it up, to see how close it gets.

If I do need more room at the front and rear of the wheel arches, am thinking about incorporating side protection/brush bars into custom lower front fenders, in a similar way to how some 40 series owners do it to their trucks.
 
i will being posting up some pics of the weak point on the troopy rear frame that i found on my build thread.

yours is going to be one wicked wicked ride (said in the best way possible), i would love to fly down someday and go for a trip with you.

cheers
 
i will being posting up some pics of the weak point on the troopy rear frame that i found on my build thread.

yours is going to be one wicked wicked ride (said in the best way possible), i would love to fly down someday and go for a trip with you.

Thanks Wayne.

Keen to see the weak points you have found in the rear frame, and how you deal with it.

Your information in that Troopy build thread about the rear winch install is going to be very useful for me in explaining what I plan to do to my Troopy to the engineer (for on road rego purposes) and to the fabricator that I get to build it for me. Your ideas are the closest I have found to what I had planned, almost exactly what I want to do in terms of having the rope run through the rear crossmember, and bracing the winch cradle back to the chassis rails.

Hopefully I might manage to ship my truck up to North America for a future holiday, and then can come out driving with you guys up there.
 
I really like those axles......


Sweet Pea in Texas has them under his fj40 and they work really well even using leaf springs.

I watched him climb a couple ledges and made most obstacles look easy.

Rob
 
I really like those axles......


Sweet Pea in Texas has them under his fj40 and they work really well even using leaf springs.

I watched him climb a couple ledges and made most obstacles look easy.
Nice!

Do you know if he has anti-wrap bars on them, to prevent axle/leaf wrap due to the leaves and the additional leverage from the offset/dropped portal boxes/wheel?

That is something I have to sort out and plan for the rear leaves on my truck.

I don't plan to go crazy doing comp style rock crawling with my truck, but it should make it easy to get in/out on rutted up tracks created by 35's/37's on standard diffs.
 
Nice!

Do you know if he has anti-wrap bars on them, to prevent axle/leaf wrap due to the leaves and the additional leverage from the offset/dropped portal boxes/wheel?

That is something I have to sort out and plan for the rear leaves on my truck.

I don't plan to go crazy doing comp style rock crawling with my truck, but it should make it easy to get in/out on rutted up tracks created by 35's/37's on standard diffs.

Off hand I cannot remember, but my guess is yes as his rig is a buggy...

Its Killerpee, not sweetpea.http://www.pirate4x4.com/forum/showthread.php?t=283509&highlight=cruiser+volvo+portals

Rob
 
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I f**king hate the seller, I hope he dies a slow and painful death.

Great project, such a shame about the idiot in the UK.

Now, if you want to invest some of your pennies, I'm sure I could arrange to have his kneecaps removed............

OK, maybe not!

That link to that LR build is incredible - that is some serious wonga invested there

:cheers:
 
looks like a serious case of fraud to me they have covered up everything you do not accidently put a 304/306 DIFF with a 303 front diff :( .

The slow ratio DIFFS you do not want - I have them and will be changing them when I have the funds.

66kph at 3000 revs in 4th is the most economical speed I can run at - and it only consumes 1 liter per 5.1k at this speed. I will check next weekend if the carby rebuild makes a difference.

Volvo Pumkins are available from China you want a price - I believe its $5,000rm for a pair of high ratio 5.0 pumpkins here. USD is about $1600.
 
looks like a serious case of fraud to me they have covered up everything you do not accidently put a 304/306 DIFF with a 303 front diff :( .
No, he sent front and rear 304/306 diffs. Both were the same 7.10:1 ratio.

Yes, I would say it was fraud, but I don't think there is much I can/could do about it when he is in the UK and I am in Australia, and he is claiming that he sent what he promised he would.


The slow ratio DIFFS you do not want - I have them and will be changing them when I have the funds.

66kph at 3000 revs in 4th is the most economical speed I can run at - and it only consumes 1 liter per 5.1k at this speed. I will check next weekend if the carby rebuild makes a difference.
Yes, the 7.10:1 ratio instead of the 5.99:1 ratio was probably the worst (and most depressing) thing about it.

I probably could have lived (very reluctantly) with the centred offset reat diff, but the 7.10:1 ratios were not going to work at all.


Volvo Pumkins are available from China you want a price - I believe its $5,000rm for a pair of high ratio 5.0 pumpkins here. USD is about $1600.
Thanks cicak, but I think I am OK at the moment, the guy that is cleaning up the mess for me has sourced 5.99:1 centres, and has removed the crownwheels and pinions to send down to me, along with the right hand offset rear axle housing (minus portal boxes) and half shafts.

I'll have to pay for the freight to get these replacement parts from the UK to Australia, but better than having to pay for replacement parts from Europe or somewhere, plus the freight to get them here. I was quoted something like $2500 per 5.99:1 crownwheel and pinion from someone in Europe.

Once I get these replacement parts from the UK, I'll have to pull my rear axle apart, get a diff specialist to swap the 7.10:1 crownwheel and pinion out and put the 5.99:1 in, then reassemble it all into/onto the correct/replacement right hand offset rear axle housing. Will also have to swap out the crownwheel and pinion in the front axle as well.
 
Hello SimonInAustarlia,
You are entering an endeavour with little if any history to back you up; i wish you the best. I am somewhat doing the same thing with my Troopy, and find i wonder at times if i am doing the right thing. Stick to your guns, right or wrong it's good to go in the whole hog. And if we are wrong, well, back to work we go to pay for repairs or more mods!

Cheers, 61Mk+
 
As the current owner of my third portal axle vehicle I can say their is no substitute for clearance. Presently I have a 1972 Pinzguaer and prevous to that a 1969 unimog 404 and a 1955 Unimog 401. I have competed in several mud bogs with the unimogs and have the trophies to prove it, beating much more expensive trucks with far more power and bigger tires. (never won on time always distance)

On the flip side I have also broke snow trails in the mountains dragging 2 well built Jeeps on a tow rope behind me. Only to realize the potential danger looming for everyone involved had the Unimog got stuck or broke down.

I seriously debated over the axle tek portals for my BJ74 before buying the Pinzgauer. It's still too soon to know if I made the right decision as I have not been able to put the Pinz to the test yet.

I will be watching your build closely, good luck!!
 
It is neat to witness the off road ambitions of various people. Your interest is good to see, and here's a reminder you don't need: do it your way, come hell or high water.

Cheers, 61Mk+
 

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