Melling 10553 vs 10553ST oil pumps; is the 10553 discontinued?

[Gary B.]

The frequently recommended Melling 10553 oil pump for SB Chevy is not available at Summit or JEGS. I’m not sure if that’s permanent or not. But both vendors now sell the Melling 10553ST, where the ST stands for shark tooth, which describes a new gear design which Melling claims increases volume by 10% to 25%. Regardless of those claims, the 10553ST pump is described as a high pressure pump. The description of the old 10553 pump on the Melling website says “To change pump to lower pressure … install the supplied yellow spring.” The 10553ST description on the JEGS and the Summit websites make no mention of being able to convert the 10553ST to a standard pressure pump via a spring replacement. Has anyone recently purchased the new Melling 10553ST oil pump who knows whether it can be converted to a standard pressure pump?


I know one option is to buy a Melling M-55 standard pressure/standard volume pump, but that seems like a big step down in quality, based on the fact it costs less than 1/3 of what the 10553 used to sell for and what the 10553ST currently sells for.

Finally, GM oil pump # 93427692 does’t seem to be an option since that pump has M55 embossed on it, which suggests it’s the Melling M55 pump, but at triple the cost of the Melling item.

Thanks,


Gary

[Larry M.]

Re: Melling 10553 vs 10553ST oil pumps; is the 10553 discontinued?

A spring change will reduce the pressure of the pump. So it should work out fine for you. Call Melling regarding what springs are shipped in the box.

But no personal history with the new design.

Larry

[Joe L.]

Re: Melling 10553 vs 10553ST oil pumps; is the 10553 discontinued?

The frequently recommended Melling 10553 oil pump for SB Chevy is not available at Summit or JEGS. I’m not sure if that’s permanent or not. But both vendors now sell the Melling 10553ST, where the ST stands for shark tooth, which describes a new gear design which Melling claims increases volume by 10% to 25%. Regardless of those claims, the 10553ST pump is described as a high pressure pump. The description of the old 10553 pump on the Melling website says “To change pump to lower pressure … install the supplied yellow spring.” The 10553ST description on the JEGS and the Summit websites make no mention of being able to convert the 10553ST to a standard pressure pump via a spring replacement. Has anyone recently purchased the new Melling 10553ST oil pump who knows whether it can be converted to a standard pressure pump?


I know one option is to buy a Melling M-55 standard pressure/standard volume pump, but that seems like a big step down in quality, based on the fact it costs less than 1/3 of what the 10553 used to sell for and what the 10553ST currently sells for.

Finally, GM oil pump # 93427692 does’t seem to be an option since that pump has M55 embossed on it, which suggests it’s the Melling M55 pump, but at triple the cost of the Melling item.

Thanks,


Gary

Gary------

I do not recommend any high volume oil pump for street small blocks. So, for me, the 10553ST would be out-of-the-question even if it can be converted to standard pressure (which I'm pretty sure it can).

I think the 10553 might still have had M55 embossed on the body. If so, the GM pump is probably the 10553.

What's wrong with your original pump? Often times these are fine for continued use. By definition, these are a well lubricated component and suffer little wear as long as oil change intervals are followed. Wear or damage is usually pretty discernible to the eye.

[Gary B.]

Re: Melling 10553 vs 10553ST oil pumps; is the 10553 discontinued?

[Robert P.]

Re: Melling 10553 vs 10553ST oil pumps; is the 10553 discontinued?

Gary , my rebuilder last year put a std M55 pump in my L79 , 60 psi cold 30 psi warm , running 30 weight vavoline racing with high zinc content
Bob

[Gary B.]

Re: Melling 10553 vs 10553ST oil pumps; is the 10553 discontinued?

Bob,

Did your engine builder use the spring that came with the M55 pump? Does 60 psi peg the oil gage needle?

gsry

[Stewart L.]

Re: Melling 10553 vs 10553ST oil pumps; is the 10553 discontinued?

The Melling tech assistance line was very helpful with a question I had regarding what pump and spring to use. Give them a call.

[Gary B.]

Re: Melling 10553 vs 10553ST oil pumps; is the 10553 discontinued?

I was able to track down a new/discontinued 10553 pump that an engine rebuilder had in inventory.

Gary

[Donald H.]

Re: Melling 10553 vs 10553ST oil pumps; is the 10553 discontinued?

I have the same issue. We are gathering parts for an L79 build in a friends 66 convertible. I've searched for the 10553 but as Gary found out, they are not available.

I exchanged messages with a Melling tech and as follows, the only difference between the 10553 and 10553ST is same pump just helical gears instead of spur gears


Brian Shimkus (BShimkus@melling.com)
To:youDetail

[Gary B.]

Re: Melling 10553 vs 10553ST oil pumps; is the 10553 discontinued?

Don,

The statement by the Melling person is very interesting because just mast month I definitely read somewhere on the web that the new shark tooth gear design in the 10553ST pump increased volume by 10% to 25%, which I didn’t want.

In looking at the Melling website today, it appears to me that Melling has a lot of newly released descriptions of the shark tooth oil pumps on their website with all sorts of pressure, volume, and oil pan depth options.

https://www.melling.com/sharktoothpumps/

Perhaps we are in luck if the the 10553ST is really a standard volume pump, that can be configured as a standard pressure pump by replacing the spring it comes with by default.

Gary

[James W.]

Re: Melling 10553 vs 10553ST oil pumps; is the 10553 discontinued?

Just ordered a Melling M55 oil pump from Rock Auto. Don't know if it will come with the extra spring or not. If it isn't correct, I'll send it back.

James

[Gary B.]

[Jack H.]

Re: Melling 10553 vs 10553ST oil pumps; is the 10553 discontinued?

I don't know if its still a "thing", but at one point in time, manufacturers went to an inferior casting design with thinner section at critical location for these pumps. It was one of the reasons why many switched from the M55 to the 10553 pumps. I'm curious to see how the new pumps compare, in particular the M55 Melling that James ordered from Rock Auto.

The differences are clear when looking just to the right of the mounting bolt bosses in the following picture...notice the thinner section on the pump at the top vs the pump at the bottom.

DSC01152a.jpg

[Gary B.]

Re: Melling 10553 vs 10553ST oil pumps; is the 10553 discontinued?

Jack,

Something accounts for the $75 difference in price. Whether the beefier casting is needed for our classic, lightly driven cars is another question.

Gary

[Dan D.]

Re: Melling 10553 vs 10553ST oil pumps; is the 10553 discontinued?

The weaker M55s have a history of breaking - which is nasty if that was to occur. I bought the 553, based on this info, just for additional insurance. I replaced to heavy spring with the green one, and in my opinion, I think the pressure is still too high. I am running a fuel unit, and high pressure can blow the seals out of the distributor cross shaft, but so far so good.

Hope this helps you.

Dannnnn