Anyone have good luck with the Thump Racing Belt Tensioner

My VMP unit has failed. Noticed it last night when I was replacing the belt. Pretty good chunk of metal missing.

Ordered an ARS this morning to be here tomorrow to make a track rental on Sunday.

mikevec87 said:

Yep that’s him . I’m not sure why people say they have a life time warranty Because they don’t and not only is it not free he will try to rip you off. I’m extremely disappointed and I’ve talk to many others that realized theirs thump tensioner was also shot after watching my video.

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I call bullshit on the new owner thing then, I bought mine 4+ years ago

mikevec87 said:

Yep that’s him . I’m not sure why people say they have a life time warranty Because they don’t and not only is it not free he will try to rip you off. I’m extremely disappointed and I’ve talk to many others that realized theirs thump tensioner was also shot after watching my video.

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Shit, I thought that was one of their saving graces of being a $500 tensioner?
Well I guess my gripes with ARS aside, I am happy it was a remotely painless thing compared to yours. And they actually have it in writing it has a lifetime warranty. Just pay return shipping

The Steeda tensioner on my '08 just let go. Should I replace it with a new tensioner, or can I just go with a shorter belt instead? Maybe the Gates 84.2"? The pulley is a 2.7" and the belt looks to be the stock 84 7/8 (7R3V-8620-AA).

rallen said:

The Steeda tensioner on my '08 just let go. Should I replace it with a new tensioner, or can I just go with a shorter belt instead? Maybe the Gates 84.2"? The pulley is a 2.7" and the belt looks to be the stock 84 7/8 (7R3V-8620-AA).

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this isn’t the same thing as what the thread is about.
I would contact Steeda and see what kind of warranty they have. They may just replace it for you free of charge.
For that type of aux idler tensioner I have the Metco. I can say I’d prefer the style like Steeda/VMP has due to infinite adjustment.
Plain and simple, deff replace it rather than a shorter belt.

My vmp unit stripped. I had a thump that got lost in the mail when I sent it in for repair and now I just ordered a ARS to try that out


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deepblue13 said:

My VMP unit has failed. Noticed it last night when I was replacing the belt. Pretty good chunk of metal missing.

Ordered an ARS this morning to be here tomorrow to make a track rental on Sunday. View attachment 1612854

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Looks like a machined steel body would do a better job than any cast or machined aluminum billet would do.

I forget where I read this, but I read ARS made all the above tensioners anyway, just to the requested standards/quality requested by the seller.
Make sense why the Thump and VMP break at the same spots? I think BJ maybe told me this or Van.

Tob said:

Looks like a machined steel body would do a better job than any cast or machined aluminum billet would do.

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Totally agree about making certain parts out of steel instead of aluminum.

Question. Have these that broke seen any unusual abuse, bumping off the limiter, racing etc?

HillbillyHotRod said:

Question. Have these that broke seen any unusual abuse, bumping off the limiter, racing etc?

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Even if they have, isnt that kind of the point in upgrading to these $500-550 tensioners? The whole point of their existence is to take the abuse that the stock ones cannot.

PM-Performance said:

Even if they have, isnt that kind of the point in upgrading to these $500-550 tensioners? The whole point of their existence is to take the abuse that the stock ones cannot.

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It is, but it's hard to make a part bullet proof when it's subject to this sort of stress..


Now consider how much power a Ford can exert on the tensioner.

Catmonkey said:

It is, but it's hard to make a part bullet proof when it's subject to this sort of stress..


Now consider how much power a Ford can exert on the tensioner.

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People aren’t buying these just to have and blow the money on for no reason. They buy them hoping they fulfill the claims of being bulletproof and hold more boost.
ARS I believe even says they guarantee theirs not to break and they never seen them break and cover them if you do. So the claims are there.

That being said, I really do not think from a design standpoint a an alum casing with a super high strength spring standing up to much banging off the stops. Hence probably why the VMP/Thump ones break as much. I think they are a bit thinner than the ARS. Or so I have been led to believe.

Mine's about six years old and when I take a belt off for maintenance or a pulley change or whatever, it does not move as freely as it did when it was new. If mine jumps like that COPO, I could see it breaking. I see a lot of what appears to be belt dust and wonder if that's not what's causing decrease in movement. Everything wears out sooner or later. Lifetime warranty is a great sales pitch, but if you're going to pitch it, you better stand behind it. I'm just pointing out these things take a whole lot more abuse than you'd suspect, especially when drag slicks are involved.

I have a tensioner stamped with the Ford logo. I bought it used and was told it was off the SCJ, but i've never found anything that matches is for sale, ever. It is made of aluminum but holy hell is it beefy. I've always wondered who ford have make it. Find out who made that and maybe we all win.

For the ones with the chunk of metal missing near the spring pigtail, I'd say it was a belt that was the improper length. How else is the tensioner arm going to hit the end of its travel?

fullboogie said:

For the ones with the chunk of metal missing near the spring pigtail, I'd say it was a belt that was the improper length. How else is the tensioner arm going to hit the end of its travel?

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I’d agree with this as well. I tend to go to shorter belts than longer for this reason. To accommodate for stretch.

I just did the basic bolt ons on my 13, used the VMP 2.4 upper and their 90mm idler. It definitively is already creating alot of belt dust and I can smell it burning after a few hard accel runs. I never had belt dust before and you can see alot of powder around the sc snout after only a few hours of hot driving. Ive only put 400 or so miles on it so far with the pulley upgrade so the belt will surely be toast in no time. It is however the factory belt that has 20,000 hard miles on it and it is now 7 years old. I dont know if it just needs replacing because the belt is old... I would like to get a gates blue one. What have yall had good experience with? I am still running the factory tensioner. Thanks

Sorry OP, didnt mean to highjack the thread man!

fullboogie said:

For the ones with the chunk of metal missing near the spring pigtail, I'd say it was a belt that was the improper length. How else is the tensioner arm going to hit the end of its travel?

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A great D.O.B write-up on tensioners answers this:

Belt Tensioner Tech