[r3ckl355]

Originally Posted by Rahul Rao

@Ashley2
Has any one tried to have lift axles with double tyres. I have seen flat bed trailers with a crude lift mechanism, where the wheels are jacked up, and a pin placed below the leaf spring which is held by bush at one side and free sliding at other.

Lift Axle with double tyres is not present in India at the moment!
Volvo and Mack have this Dual tyre Lift Axle in some countries!

Originally Posted by silversteed

Two questions:
1. Why isn't the lift-axle fitted ahead of the live axle, and not behind RA2 (live axle 2, if it's an 8x4)? The latter option will solve the issue of having limited WB and loading span options.
2. For the 3718il and 3723, why has AL placed the lift-axle ahead of the live axle, while TM has placed it behind RA2? I saw this portrayed as an advantage with the TM version, as pusher-type lift axles cause additional tyre wear.

The BB 3123R 8X4 has the lift axle in front of the Tandem Bogie Rear Axles!
The rest of the questions have been answered by Ashley I guess!



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[silversteed]

Originally Posted by r3ckl355

Lift Axle with double tyres is not present in India at the moment!

TM had showcased their LPS4923-LA tractor with a double-tyred lift-axle:



It's not commercially available though.

Originally Posted by r3ckl355

Volvo and Mack have this Dual tyre Lift Axle in some countries!

Here's a Kenworth and a Ford Transcontinental 4435, having lift-axles with double tyres:



The Kenworth is pretty popular in the US.




This Ford did not sell well, and very few are on the roads now. It was fairly advanced for its time (1980s), just like AL's Sitibus when introduced in India

Image Credit: Respective owners

[directinjection]

Originally Posted by r3ckl355

Lift Axle with double tyres is not present in India at the moment! Volvo and Mack have this Dual tyre Lift Axle in some countries!

Originally Posted by silversteed

TM had showcased their LPS4923-LA tractor with a double-tyred lift-axle: It's not commercially available though.

Way back in 1981, TM had displayed a rigid three axle truck in which the middle axle was a dual tyre lift axle. Those were pre Auto Expo days. The truck was displayed at India International Trade Fair, Delhi. The model was called 1812. However, I never saw in on road and guess it was also not commercially launched. Incidentally, 1812 used the same cab which 4923 in your pic uses with some minor modifications!

[r3ckl355]

Originally Posted by silversteed

TM had showcased their LPS4923-LA tractor with a double-tyred lift-axle:

Attachment 1303906

It's not commercially available though.

I was not aware of this Tata tractor!! When was this showcased?

I think other manufacturers too also offer dual lift axle,
like this Renault 450.25 6X2 & the Scania P310 Rigid



Can you shed some more light on sitibus?

[sadsack]

Originally Posted by 1100D

Imagine reversing an articulated through a narrow gate. Sometimes the additional length of the articulated is a problem while taking turns, whereas the length might not be required to carry the additional payload.

Besides this the overall skill required to drive an articulated is higher, could make finding the driver more difficult!

No Sir, in greater number of situations the articulated truck is a better option than the rigid chassis truck. Length is an issue in both varieties. In order to add the extra number of axles the chassis is necessarily longer in the rigid truck. In turns the articulated truck has a much smaller radius than the rigid ones. A longer articulated truck can turn better (because of the smaller radius) than not only a comparable rigid truck but also some of the slightly smaller rigid trucks.

Reversing through a narrow gate is not a situation that is likely to encountered because most cities now do not allow trucks of a certain size right upto the place where delivery is to be made and even if they are allowed trucks do not enter compounds of buildings.

I do not think nifty is a term that can be used in the contexts of trucks be they rigid or articulated. I think the requirement of better trained drivers for the articulated trucks is actually a good thing, because that means the roads will be that much more safer. If more truck operators buy articulated trucks rather than multi-axle rigid trucks obviously the drivers will also be forced to learn to drive better. Otherwise it will be a situation of the tail wagging the dog.

[silversteed]

Originally Posted by directinjection

Way back in 1981, TM had displayed a rigid three axle truck in which the middle axle was a dual tyre lift axle. Those were pre Auto Expo days. The truck was displayed at India International Trade Fair, Delhi. The model was called 1812. However, I never saw in on road and guess it was also not commercially launched. Incidentally, 1812 used the same cab which 4923 in your pic uses with some minor modifications!

Interesting! Never heard of such a model ever.

Originally Posted by r3ckl355

I was not aware of this Tata tractor!! When was this showcased?

Auto Expo 2014

Originally Posted by r3ckl355

Can you shed some more light on sitibus?

Check posts 300, 304 and 305 in this thread

[1100D]

Originally Posted by sadsack

No Sir, in greater number of situations the articulated truck is a better option than the rigid chassis truck. Length is an issue in both varieties. In order to add the extra number of axles the chassis is necessarily longer in the rigid truck. In turns the articulated truck has a much smaller radius than the rigid ones. A longer articulated truck can turn better (because of the smaller radius) than not only a comparable rigid truck but also some of the slightly smaller rigid trucks.

Reversing through a narrow gate is not a situation that is likely to encountered because most cities now do not allow trucks of a certain size right upto the place where delivery is to be made and even if they are allowed trucks do not enter compounds of buildings.

If you note, there was another post after the one you quoted

Originally Posted by 1100D

2 fleet owners I know in our area from a long time. Have switched to 4 axle rigids as they are not allowed to overload their 2/3 axle rigids anymore. Articulated trucks would not make it to their yard which is close to my home, infact articulated trucks cannot make it within 5 km of the area.

I am speaking from personal knowledge of 2 fleet operators. Besides, you need to think beyond the big cities, the smaller towns, narrow lanes (Something like Dumka, Bhagalpur) and articulated truck entering those towns actually cause Hindrance (given that for many turns even Rigids need backing up). Narrow gates are not made by choice but due to inadequacy of approach.

Originally Posted by silversteed

I think an articulated 40T or 49T truck is not a replacement for a 37T rigid (and vice versa), as both are used for slightly different purposes. The former is used for large-sized cargo while the latter is for dense but smaller one.

Like 1100D said, a trailer truck is a pain to drive around in congested places, whereas a rigid has its advantages in last-mile connectivity.

But as Silversteed has rightly mentioned, its not that either can replace the other, each having its own set of usage and the fleet operators are actually quite adept at choosing what they need.

[Ashley2]

Originally Posted by Rahul Rao

@Ashley2
Has any one tried to have lift axles with double tyres. I have seen flat bed trailers with a crude lift mechanism, where the wheels are jacked up, and a pin placed below the leaf spring which is held by bush at one side and free sliding at other...

AL showcased a concept of lift axle in 10T axle and that too in a live axle unlike the dead ones in tractor trailer in Auto Expo 2010. This 49T Tractor head was called as Effi 20, and it had various innovations for fuel savings to the tune of 20%. That includes super single duos rear tyres with alloy wheels, dynamic ECU mapping, newer and optimized cooling fan etc.. These are validated and certified by ARAI. These features were split and is now adopted in various newer models.

[Rahul Rao]

Rigids are more popular here due to taxation and such reasons. In fact if you consider chassis cost / ton, GVW to Payload ratio, the articulating trucks are cheaper.
Secondly many countries do not allow the trailing axle load to exceed the tractor load by 20%, so trailers like 4018 with a 6 tyred 16T tractor and 12 tyred 24 Ton trailer cannot be registered. There you will see a 10 Tyred tractor and a 8 tyred trailer which with our rules should give a 44 Ton Gross capacity.

In pre ABS days very heavy trailer pulled by a tractor with lesser load would push the tractor out of line during heavy braking.

Rahul

[tharian]

Spotted these two 5 axle Leylands on the way to Tumkur.

One was with a factory cowl and short rear overhang and another was a longer one with the same set up ,but a fully non OEM cab.

I noticed, unlike few years ago, the 3 axle trucks are very less on the highways. Majority of the rigid trucks I spotted were the 4 axle ones along with a good number of the 5 axle types.
The old rear single axle is almost non existent.

[sagarpadaki]

Have seen an increase trend in number of these trucks on our highways. Looks like higher load capacity coupled with lesser tire wear due to better distribution of loads is making them a hit!