Do tractors adhere to GVW ratings?

[TSO]

I was browsing thru my manual, and noticed that my rear and front axles have the same weight rating (4,630# each). I was thinking that was odd...I would have assumed that my rear axle would have a heavier rating.

Trucks have to abide by different GVW ratings depending on which class they are in; for example, typically F250's stay under 10k lbs, even tho adding one leaf to the rear from the factory (F350) can boost your GVW by a couple thousand lbs... Yet, adding springs aftermarket won't legally change your GVW.

Are tractors similar?

I can't think of another reason why my front and rear axle would have the same rating ... Seems like an amazing feat of engineering if they were truly designed and manufactured to handle the same exact weight, being how completely different they are in application and design.

 

[geneP]

There is a DOT to enforce weight rating on trucks, I don't know who would enforce them on a tractor unless there is a truth-in-advertising law. I suspect the tractor front axle is rated similar to the rear for FEL consideration.

 

[MHarryE]

Weight capacity on front axles needs to be very high despite the smaller tires because so many get loaders, especially in the small utility class. It's not a legal thing like a vehicle, but rather a rating as to what load the axle is actually capable of handling.

 

[GManBart]

I think if you measure just the axle housings front and rear, they're closer in size than you'd expect. The rear looks bigger because the differential is so massive, but the axle housings out near the wheels are quite a bit smaller...and that's the point that matters (weakest/smallest). The actual axles themselves don't really matter, since they transfer power, rather than carry weight.

 

[Opti-Mist]

There is no specified Gross Axle Weight Rating (GAWR )for tractors as there is for trucks. The tires end up being the limiting factor. As the good doctor from Firestone said years ago "A tire is a pressure vessel." Watch your front tires squat when you are using your loader and you get a little nervous as the squat increases with greater loads.

 

[Soundguy]

Another issue to think of on the rear of the tractor is the weight it can handle on a swinging drawbar, if equipped, and how that limit is effected by lenght / leverage. Don't want to rip the bottom out of the rear center section... etc

 

[arlen4720]

I was browsing thru my manual, and noticed that my rear and front axles have the same weight rating (4,630# each). I was thinking that was odd...I would have assumed that my rear axle would have a heavier rating.

That is odd (to me at least). I think it is great that the front axle is rated that high.
My JD 4720 manual says:
Front Axle 3528 lb, and Rear Axle 5292 lb. It says "continuous" in parentheses for whatever that's worth

It seems like not many CUT manufactures list the axle ratings, or at least so it seemed when I was shopping around; I wish they would.

 

[TSO]

That is odd (to me at least). I think it is great that the front axle is rated that high.
My JD 4720 manual says:
Front Axle 3528 lb, and Rear Axle 5292 lb. It says "continuous" in parentheses for whatever that's worth

It seems like not many CUT manufactures list the axle ratings, or at least so it seemed when I was shopping around; I wish they would.

I agree, me and a friend have been trying to find the axle ratings for his kubota L3540, but we can't find any of the axle ratings for any of the grand L tractors.

Arlen, does your book list the gross combined actual rating? The 2 of mine don't add up, my gross combined number is listed I believe at 8370. But if you add up the individual ratings it would be 9260.

Mine doesn't say anything about continuous, just the one printed rating. It also lists the weight distribution of the tractor between the front and rear.

 

[jenkinsph]

Arlen, does your book list the gross combined actual rating? The 2 of mine don't add up, my gross combined number is listed I believe at 8370. But if you add up the individual ratings it would be 9260.

I would not expect the front and rear ratings summed up to equate to the overall or gross ratings in all cases. A conservative rating is often slightly lower than the sum of the parts, if you look at the tire ratings and add them up they would likely be higher than the axle ratings too. Static load ratings would be higher than dynamic load ratings too, if you hit a bump with one wheel the manufacturer wants the gvw to be low enough to deal with this added stress.

 

[David Devuono]

Id just take the weight of the tractor and add the weight capacity of the Loader and 3PTH. I would not think that Loaded tires would matter. So if My B3200 weight 2500lbs with loader and the 3PTH and loader can handle 1,000 each so the tractor is likely designed for 4500 lbs operating weight. Basic limitations I see are for Loader, 3PTH and trailer tow capacities. The rest is up to you and the ROPS to sort out.