Weight over front axle
- dandjcr
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31 Oct 2012 21:10 #1
by dandjcr
David and Janet Ribbans - Oka 148
Oka148 profile here.
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dandjcr created the topic: Weight over front axle
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joseph baz
Member
Posts: 331
Hi All,does anyone know what the typical weight over the front axle is on a XT-LT bus body?
Cheers,Joe
August 9, 2011 at 7:44 AM Flag Quote & Reply
Dandj
Member
Posts: 367
Joe, couldn't find any actual weights but going by the axle specs in the Oka manual, the weight distribution is about 3100kg rear and 2400kg front (ie GVM 5500kg).
This assumes an evenly spread, maximum load.
The NT specs show the about the same ratio but higher weights, 56% rear, 44% front.
--
David and Janet Ribbans, Oka 148
August 9, 2011 at 9:02 AM Flag Quote & Reply
Tony Lee
Member
Posts: 539
That would be the weights with the bus full of 'standard' passengers and some luggage.
--
Tony
picasaweb.google.com/114611728110254134379
August 9, 2011 at 4:55 PM Flag Quote & Reply
joseph baz
Member
Posts: 331
Thanks for the info,David and Tony,the department of transport wants a weightbridge certificate from before I started the engine converssion and I don't know were I put it, for safe keeping (must be really safe),BTW the Mercedes convoy of G wagons arrived in Halls Creek this afternoon and they don't want to talk about the suspension problems
Cheers,Joe
August 9, 2011 at 7:10 PM Flag Quote & Reply
Ewart & Vivian Halford
Member
Posts: 117
Joe, I had my single cab ute weighed in Kalgoorlie and it came in at 3960KG
Front 2440 KG Rear 1520 KG
I then had it weighed down here a few week ago without the tray
Front 2340 KG Rear 900 KG Total 3240 KG, Tray weighs 720 KG.
Acording to my LT manual a full bus body without passengers and roof rack weighs 943 KG that does not include the cab, it weighs 638 KG.
Hope that helps
Ewart
August 9, 2011 at 11:02 PM Flag Quote & Reply
joseph baz
Member
Posts: 331
Thanks for the info Ewart,They won't take my word for it so until I find the weightbridge ticket nothing will progress.
Cheers,Joe
August 10, 2011 at 9:29 PM Flag Quote & Reply
Ewart & Vivian Halford
Member
Posts: 117
Joe, would you be able to get something off OKA?
Ewart
August 10, 2011 at 10:03 PM Flag Quote & Reply
OKA 262
Member
Posts: 27
Hi Joe
I have actual weigh bridge figures for our Oka. Its a motorhome conversion with a glass fibre sandwitch module attached to a cab chassis. It weighs in at 4970kg with a front to rear axle weight distribution of 2460/2510kg. In full expedition trim it weighs in at 5490kg. Don't have axle weights for this weight.
Stay well
Vidas
August 10, 2011 at 10:16 PM Flag Quote & Reply
joseph baz
Member
Posts: 331
Thanks Vidas,your weight will be very close to my finished product as the motorhome part will be virtually the same as yours in size and type of material.
Cheers,joe
August 11, 2011 at 2:17 PM Flag Quote & Reply
Peter_n_Margaret
Member
Posts: 198
According to the XT manual, the axle ratings are 2,400kg (front) and 3,100kg (rear).
BUT...... is that the Spicer ratings or the OKA maximum loads.
What is required to increase the GVM? Where is the 'weak point' from an engineering perspective?
--
Cheers Peter, OKA196 Motorhome. www.oka4wd.com/xt196.htm
September 20, 2011 at 10:23 AM Flag Quote & Reply
Peter & Sandra James Oka 374
Member
Posts: 412
Typical Spicer load ratings for the rear Dana 70 axle housings are 7500lb (3400 kg) and the heavy duty versions are 10000lb(4500kg). I suspect the the Oka versions are the earlier lighter ones at 7500lb on the rear but 2400lb on the Dana 60 front axle.
As Oka's typically have 32 spline drive axles they are at the lighter end of the range.
Working out what versions the Oka has is where the problem lies as there are so many variations.
Then you get the situation where some LT's have a GVM of 6,000kg (which ours 374 does).
What if anything was done to increase the axles carrying capacity? I haven't had any of our axles apart to see whether they are 32 or 35 spline which I would imagine is the only change Oka may have made, certainly the housings appear to be identical.
--
Oka 374 LT Van
September 20, 2011 at 3:18 PM Flag Quote & Reply
Aussie Bight Expeditions
Member
Posts: 109
From what I have been told is that the load ratings are set by the axle manufacturer not OKA. Axle spline numbers have nothing to do with the calculation so I was lead to believe. It is the size of the tube that the axle passes through that determines the load rating. 80 series diffs run the same axles different rack and pinion gear as they are heavier, and the tube size from the 60 to the 80 series that a few people have put in are say 9/16" thick instead of 1/2" thick. They might not be the dimensions as I can not remember that part, but the thickness of the tube increases the load rating. You can increase the load rating by putting airbags on as they did for Rudy's NT001, as he had alot of extra weight over the front and that was how they eventually got that rating higher so it could be registered. Regards ABE TONY
September 20, 2011 at 3:45 PM Flag Quote & Reply
joseph baz
Member
Posts: 331
Aussie Bight Expeditions at September 20, 2011 at 3:45 PM
From what I have been told is that the load ratings are set by the axle manufacturer not OKA. Axle spline numbers have nothing to do with the calculation so I was lead to believe. It is the size of the tube that the axle passes through that determines the load rating. 80 series diffs run the same axles different rack and pinion gear as they are heavier, and the tube size from the 60 to the 80 series that a few people have put in are say 9/16" thick instead of 1/2" thick. They might not be the dimensions as I can not remember that part, but the thickness of the tube increases the load rating. You can increase the load rating by putting airbags on as they did for Rudy's NT001, as he had alot of extra weight over the front and that was how they eventually got that rating higher so it could be registered. Regards ABE TONY
you are right Tony the axle loading is set by the manufacturer,once they
rate an axle any improvement by any outside parties is not of any significance and the authorities will not recongnice it.
Cheers,Joe
September 20, 2011 at 9:12 PM Flag Quote & Reply
Hal Harvey
Site Owner
Posts: 510
Joe was asking about the front end (Dana 60) because that’s where he’ll have the load challenge – NT001 has different diff assemblies. Wikipedia says this which includes the line “Gross axle weight ratings (GAWR) are often lowered by the vehicle manufacturer for safety and tire reasons” – but doesn’t say what Dana have as a weight rating for the 60 front. Read through that lot and you’ll see it’s not just Oka that had a few variations on the theme when it came to axle setups!
Dodge rated them at 4500lbs, 4850 or 5200lb depending on which truck they put them in the front of. The lighter ones are noted as having been related to spring capacity. 5200lb = 2360kg (remember this was still downgraded). Tube thickness is half inch. GAWR is a combination of axle rating, springs, wheels and tyres, and that’s what Joe has to fall within.
When Ford used the 60 in the front of F-450s and F-550s, they rated them up to 6000lb (2700kg); so it would appear that the springs are the limiting factor.
Wikipedia says of the 70 rear: “All Dana 70 rear axles are full floating and typically have a gross axle rating of 7500lbs” (= 3400kg, which OKA downgraded to 3100kg on the 5500GVM vehicles).
It looks to me like a 5500kg GVM OKA is a 6000lb front and a 7500lb rear, downgraded 10% = 5520kg... 2450kg on the front and 3070kg on the rear (OKA say 2400/3100). Vidas has 2460kg on the front and may have a lighter motor than what Joe wants?.. could be a problem, might need some upgraded springs Joe. Then an engineer could re-rate the GVM up to 6000lb front.
--
Hal
September 20, 2011 at 11:19 PM Flag Quote & Reply
joseph baz
Member
Posts: 331
Hal,OKA supplied me with a weightbridge certificate for the Cummins 4 cyl and the 6cyl is not that much heavier and the engineer is happy with it so....I'm happy
Cheers,Joe
September 21, 2011 at 8:30 PM
joseph baz
Member
Posts: 331
Hi All,does anyone know what the typical weight over the front axle is on a XT-LT bus body?
Cheers,Joe
August 9, 2011 at 7:44 AM Flag Quote & Reply
Dandj
Member
Posts: 367
Joe, couldn't find any actual weights but going by the axle specs in the Oka manual, the weight distribution is about 3100kg rear and 2400kg front (ie GVM 5500kg).
This assumes an evenly spread, maximum load.
The NT specs show the about the same ratio but higher weights, 56% rear, 44% front.
--
David and Janet Ribbans, Oka 148
August 9, 2011 at 9:02 AM Flag Quote & Reply
Tony Lee
Member
Posts: 539
That would be the weights with the bus full of 'standard' passengers and some luggage.
--
Tony
picasaweb.google.com/114611728110254134379
August 9, 2011 at 4:55 PM Flag Quote & Reply
joseph baz
Member
Posts: 331
Thanks for the info,David and Tony,the department of transport wants a weightbridge certificate from before I started the engine converssion and I don't know were I put it, for safe keeping (must be really safe),BTW the Mercedes convoy of G wagons arrived in Halls Creek this afternoon and they don't want to talk about the suspension problems
Cheers,Joe
August 9, 2011 at 7:10 PM Flag Quote & Reply
Ewart & Vivian Halford
Member
Posts: 117
Joe, I had my single cab ute weighed in Kalgoorlie and it came in at 3960KG
Front 2440 KG Rear 1520 KG
I then had it weighed down here a few week ago without the tray
Front 2340 KG Rear 900 KG Total 3240 KG, Tray weighs 720 KG.
Acording to my LT manual a full bus body without passengers and roof rack weighs 943 KG that does not include the cab, it weighs 638 KG.
Hope that helps
Ewart
August 9, 2011 at 11:02 PM Flag Quote & Reply
joseph baz
Member
Posts: 331
Thanks for the info Ewart,They won't take my word for it so until I find the weightbridge ticket nothing will progress.
Cheers,Joe
August 10, 2011 at 9:29 PM Flag Quote & Reply
Ewart & Vivian Halford
Member
Posts: 117
Joe, would you be able to get something off OKA?
Ewart
August 10, 2011 at 10:03 PM Flag Quote & Reply
OKA 262
Member
Posts: 27
Hi Joe
I have actual weigh bridge figures for our Oka. Its a motorhome conversion with a glass fibre sandwitch module attached to a cab chassis. It weighs in at 4970kg with a front to rear axle weight distribution of 2460/2510kg. In full expedition trim it weighs in at 5490kg. Don't have axle weights for this weight.
Stay well
Vidas
August 10, 2011 at 10:16 PM Flag Quote & Reply
joseph baz
Member
Posts: 331
Thanks Vidas,your weight will be very close to my finished product as the motorhome part will be virtually the same as yours in size and type of material.
Cheers,joe
August 11, 2011 at 2:17 PM Flag Quote & Reply
Peter_n_Margaret
Member
Posts: 198
According to the XT manual, the axle ratings are 2,400kg (front) and 3,100kg (rear).
BUT...... is that the Spicer ratings or the OKA maximum loads.
What is required to increase the GVM? Where is the 'weak point' from an engineering perspective?
--
Cheers Peter, OKA196 Motorhome. www.oka4wd.com/xt196.htm
September 20, 2011 at 10:23 AM Flag Quote & Reply
Peter & Sandra James Oka 374
Member
Posts: 412
Typical Spicer load ratings for the rear Dana 70 axle housings are 7500lb (3400 kg) and the heavy duty versions are 10000lb(4500kg). I suspect the the Oka versions are the earlier lighter ones at 7500lb on the rear but 2400lb on the Dana 60 front axle.
As Oka's typically have 32 spline drive axles they are at the lighter end of the range.
Working out what versions the Oka has is where the problem lies as there are so many variations.
Then you get the situation where some LT's have a GVM of 6,000kg (which ours 374 does).
What if anything was done to increase the axles carrying capacity? I haven't had any of our axles apart to see whether they are 32 or 35 spline which I would imagine is the only change Oka may have made, certainly the housings appear to be identical.
--
Oka 374 LT Van
September 20, 2011 at 3:18 PM Flag Quote & Reply
Aussie Bight Expeditions
Member
Posts: 109
From what I have been told is that the load ratings are set by the axle manufacturer not OKA. Axle spline numbers have nothing to do with the calculation so I was lead to believe. It is the size of the tube that the axle passes through that determines the load rating. 80 series diffs run the same axles different rack and pinion gear as they are heavier, and the tube size from the 60 to the 80 series that a few people have put in are say 9/16" thick instead of 1/2" thick. They might not be the dimensions as I can not remember that part, but the thickness of the tube increases the load rating. You can increase the load rating by putting airbags on as they did for Rudy's NT001, as he had alot of extra weight over the front and that was how they eventually got that rating higher so it could be registered. Regards ABE TONY
September 20, 2011 at 3:45 PM Flag Quote & Reply
joseph baz
Member
Posts: 331
Aussie Bight Expeditions at September 20, 2011 at 3:45 PM
From what I have been told is that the load ratings are set by the axle manufacturer not OKA. Axle spline numbers have nothing to do with the calculation so I was lead to believe. It is the size of the tube that the axle passes through that determines the load rating. 80 series diffs run the same axles different rack and pinion gear as they are heavier, and the tube size from the 60 to the 80 series that a few people have put in are say 9/16" thick instead of 1/2" thick. They might not be the dimensions as I can not remember that part, but the thickness of the tube increases the load rating. You can increase the load rating by putting airbags on as they did for Rudy's NT001, as he had alot of extra weight over the front and that was how they eventually got that rating higher so it could be registered. Regards ABE TONY
you are right Tony the axle loading is set by the manufacturer,once they
rate an axle any improvement by any outside parties is not of any significance and the authorities will not recongnice it.
Cheers,Joe
September 20, 2011 at 9:12 PM Flag Quote & Reply
Hal Harvey
Site Owner
Posts: 510
Joe was asking about the front end (Dana 60) because that’s where he’ll have the load challenge – NT001 has different diff assemblies. Wikipedia says this which includes the line “Gross axle weight ratings (GAWR) are often lowered by the vehicle manufacturer for safety and tire reasons” – but doesn’t say what Dana have as a weight rating for the 60 front. Read through that lot and you’ll see it’s not just Oka that had a few variations on the theme when it came to axle setups!
Dodge rated them at 4500lbs, 4850 or 5200lb depending on which truck they put them in the front of. The lighter ones are noted as having been related to spring capacity. 5200lb = 2360kg (remember this was still downgraded). Tube thickness is half inch. GAWR is a combination of axle rating, springs, wheels and tyres, and that’s what Joe has to fall within.
When Ford used the 60 in the front of F-450s and F-550s, they rated them up to 6000lb (2700kg); so it would appear that the springs are the limiting factor.
Wikipedia says of the 70 rear: “All Dana 70 rear axles are full floating and typically have a gross axle rating of 7500lbs” (= 3400kg, which OKA downgraded to 3100kg on the 5500GVM vehicles).
It looks to me like a 5500kg GVM OKA is a 6000lb front and a 7500lb rear, downgraded 10% = 5520kg... 2450kg on the front and 3070kg on the rear (OKA say 2400/3100). Vidas has 2460kg on the front and may have a lighter motor than what Joe wants?.. could be a problem, might need some upgraded springs Joe. Then an engineer could re-rate the GVM up to 6000lb front.
--
Hal
September 20, 2011 at 11:19 PM Flag Quote & Reply
joseph baz
Member
Posts: 331
Hal,OKA supplied me with a weightbridge certificate for the Cummins 4 cyl and the 6cyl is not that much heavier and the engineer is happy with it so....I'm happy
Cheers,Joe
September 21, 2011 at 8:30 PM
David and Janet Ribbans - Oka 148
Oka148 profile here.
Visit our technical and travel blogs: here.
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