LM48548/LM48510 Tapered roller bearing

Firstly, if you have come here wanting to buy an LM48548/LM48510 online then follow this link. This page contains information about the bearing but isn’t the product page for it.

Here, we’re going to be looking at the differences between tapered roller bearing manufacturers for the same item.

The manufacturers that we are going to look at today are Timken, SKF, NTN, NSK and Koyo who are all premium OEM bearing manufacturers and we’re going to look at the part number LM48548/LM48510 and see whether there are any differences between the manufacturers.

LM48548/LM48510 Part numbering

Firstly, let’s look at the part numbering system used.

In the bearing industry this item is commonly known as an LM48548/LM48510 which comes from the fact that the part number for the inner of the bearing or “the cone” is LM48548 and part number for the outer of the bearing or “the cup” is LM48548. For this inch sized tapered roller bearing the cone part number usually comes first followed by a “/” and then followed by the cup part number.

The LM48548 cone for example could fit not just with an LM48510 cup but could fit with an LM48511 cup making the complete part number LM48548/LM48511 or it could fit with an LM48514 cup making the complete part number LM48548/LM48514.

As you can see from the table below most manufacturers have slight variations in how they list their part numbers.

Timken separate their cone and cup part numbers and use a “ – “ to separate them.
SKF & NSK list them exactly how we have listed it on this page. This part numbering system is very common amongst other bearing manufacturers and distributors.
NTN list theirs with a 4T- at the beginning. This extra part numbering just means that the bearing is made with a special grade of case hardened bearing steel.
Koyo list theirs in a shortened form, essentially dropping some of the cup part number that is common to both the cup and the cone and just adding on the differentiating letters after the “/”. This format is especially common in the bearing distributor market where shortening the part number in this way helps to improve speed. When enquiring for this bearing on the phone for example, a customer might say. “Can you quote me with an LM48548 with a 10”. The 10 being easier to say than LM48510.

Occasionally you will also find companies that drop the letters off of the start of the bearing and just call the bearing 48548/48510. This would still mean the same thing. The LM simply means Light-Medium load denoting the weight carrying parameters of the bearing so essentially nothing is lost if those are letters are dropped when describing the bearing.

This type of different part numbering practice is common place across all types of bearings, quite often only experience can assist you in knowing how to get from the part number of one manufacturer to the part number of another.

So what else is different about the LM48548/LM48510 bearing between these manufacturers ? Well you might think that they should all weigh the same because they are meant to be the same part. That isn’t however the case.

LM48548/LM48510 Mass

The table below shows the mass catalogued from each of the manufacturer’s. As you can see there is quite a spread in terms of the mass between different manufacturers. The mass for the Koyo LM48548/10 is missing below as that wasn’t available on their online catalogue.

Does this mean that a Timken LM48548/LM48510 is inferior to a SKF LM48548/LM48510 because it weighs less ? That’s not really how bearings work. There are many more important factors at play including the precision level and finish of the component parts and the quality of the materials that they are manufactured from. In fact, Timken were the original company to make tapered roller bearings, it is their flagship product and something that they are recognized for around the world as producing with enviable quality levels. They are trusted globally amongst OEM’s and are often the first choice when it comes to tapered roller bearing selection. With the catalogued mass it’s quite feasible that the catalogue mass are computer generated rather than being actually weighed from a real component. Alternatively it’s possible that some manufacturers calculate their mass without packaging and some manufacturers calculate their weight with packaging. What we’re saying is take the catalogued mass with a pinch of salt. There are bearing series where the mass do play a part in the quality but amongst premium manufacturers like these, especially with tapered roller bearings the weight is not a factor in whose bearing is best.

LM48548/LM48510 Load Ratings

What about load ratings ? Surely if one of the manufacturers has a higher load rating for the LM48548/LM48510 bearing then that makes it better the others right ? As always with bearings it’s not quite that simple. Looking at the table below it looks like Timken is streets ahead and that NSK and NTN are lagging behind.

Well, most load ratings are calculate load ratings not tested load ratings. It’s basically taking information about the bearing, running it through a formula and the load ratings in the catalogue are a result of that calculation. That’s not to say there isn’t anything in it. Timken as I’ve mentioned before are market leads for tapered roller bearings so it certainly wouldn’t be surprising if they actually had the higher load ratings in real life but we just cannot take the catalogued figures in isolation and say one bearing is better than another.

You will be pleased to hear that one thing that does stay the same between all manufacturers is that the dimensions stay the same. Tapered roller bearings are produced to ISO 355, JIS B 1512 and ABMA standards which define the dimensions and tolerances for different types of bearings so whilst the internal geometry of the bearings might differ between manufacturers, when it comes to the overall dimensions they remain the same.

As we develop the site further we will look to put the LM48548/LM48510 bearings from each of the manufacturers on accelerated bench tests at various loads and speeds so that we can truly see whose bearings outperform the others. 

We hope that you have found this information useful. If you think it would be beneficial for us to write on another bearing related topic then please contact us and we will add it to our workflow. We are keen to make sure that we become a knowledge resource for all things bearing related and bridge that gap of requiring industry experience to navigate the minefield that is bearings.