Adding tension to your dayco tensioner

[Chevy1925]

So I needed to add more tension to my belt setup since I’m running 149” belt and 02-05 use a different idler pulley setup than the 06-up that doesn’t really let you get all the slack out of the belt. This is only an issue if you are like me and have a van thermostat housing and dual fueler

That said, I have a dayco tensioner from autozone that I know a lot of guys run as well to keep the belt on their truck. The two Allen head bolts on the back of the tensioner that set into the recesses of the accessory bracket to “key it” can be unbolted without anything coming apart. Figure out how much you want to add for tension and redrill holes clockwise from the original holes. I went 3/8” from original. You can go farther than this just by sanding off the stop that keeps you from going too far. Made a significant difference in tension from before

As you can see, I have 4 open holes. First time I added new holes in the wrong direction lol (counterclockwise, don’t go that way unless you want less tension)

May not be many guys needing this mod but think this will help those that still have jumping belt issues at high rpm or can’t get pulley alignment perfect

 

[WisconsinHick1]

Hey James does that Dayco have a metal pulley? If so what's the part number by chance? Also great mood I might need this in the future for my setup!

 

[NC-smokinlmm]

Why not go manual like I did with my LS? My belt is tight as fuk!

 

[Noreaster]

Hey James does that Dayco have a metal pulley? If so what's the part number by chance? Also great mood I might need this in the future for my setup!

Yep metal pulley
#89259

 

[prostreeter600]

What part brand and # did you use on your LS ? Where did you get it if you don’t mind . My brother’s turbo LS is chunking the belt .

 

[NC-smokinlmm]

What part brand and # did you use on your LS ? Where did you get it if you don’t mind . My brother’s turbo LS is chunking the belt .

I'll have to go back and look. It's a heafty piece, I love it, minimal loss of boost with standard belt...

I'm about to overdrive it by 10% and go 8 rib so it maybe for sale as its for a 6 rib but it may work, I'll have to see...

Has he gone to an electric water pump? How much rwhp? Most of my friends went to the e water pump to lessen belt strain and keep from cavitatating it at high rpm...

 

[prostreeter600]

He just purchased it . Trying to get the bugs worked out of it . It’s a 6.0 built 6.0 with a single 83 Bullseye.

 

[Chevy1925]

Why not go manual like I did with my LS? My belt is tight as fuk!

Don’t believe it will work well on such a long belt. The 149” only comes in a normal belt and it stretches quite a bit when hot. Do they even make a manual setup for a dmax?

And yeah Eric, it’s metal. The pulley you see on mine is metal. If not, I think you can punch the bearing out of the plastic one and put it in the factory steel one so it’s “new”

 

[rcr1978]

Thanks for taking the time to post pics, mines run the same way. It seems ok now but I have not drove it yet since there is no down pipe on it and exhaust will blow on the firewall until I finish building my twin piping. Did you hear your belt squeal under a good load James?

 

[Chevy1925]

Thanks for taking the time to post pics, mines run the same way. It seems ok now but I have not drove it yet since there is no down pipe on it and exhaust will blow on the firewall until I finish building my twin piping. Did you hear your belt squeal under a good load James?

I never did but with me running a solid fan hub now, I wanted to be damn sure it wasn’t an issue. I do know it holds less tension before the mod than the original dual fueler belt routing cause it was real close to the relaxed stop when running and hot

 

[mike diesel]

Don’t believe it will work well on such a long belt. The 149” only comes in a normal belt and it stretches quite a bit when hot. Do they even make a manual setup for a dmax?

And yeah Eric, it’s metal. The pulley you see on mine is metal. If not, I think you can punch the bearing out of the plastic one and put it in the factory steel one so it’s “new”

After tossing and shredding literally 20+ belts last season on the StarLite truck, we built a mechanical (solid) tensioner while utilizing the 149" belt. Haven't lost a single belt yet. And this belt that's been on it since day 1 with the solid tensioner still looks brand new. We tried 15 different factory style tensioners and added several more idler pulley to no avail. Solid tensioner solved every single problem.

 

[TheBac]

Alright guys, you're using old-skool V-belt technology for a serpentine-belt problem tension problem, which I think is brilliant....so would one of you please give us the low-down on just HOW you built the parts to solve this dilemma?

 

[Bbuchanan11]

Katech engines makes a lot of nice billet manual tensioners not one specifically for a duramax but might be able to get one to work... I used one on my supercharged Silverado and it stopped the belt from slipping.

 

[duramaxzak]

After tossing and shredding literally 20+ belts last season on the StarLite truck, we built a mechanical (solid) tensioner while utilizing the 149" belt. Haven't lost a single belt yet. And this belt that's been on it since day 1 with the solid tensioner still looks brand new. We tried 15 different factory style tensioners and added several more idler pulley to no avail. Solid tensioner solved every single problem.

I know this post is old, but do you or anyone have pictures or know anyone that makes a manual adjustable belt tensioner for the Dmax? I'm running the 149" belt and have lost 2 so far...

 

[gmduramax]

I can see if my katech tensioner will bolt onto my truck, or if it can be made to fit.

 

[JoshH]

ICT Billet makes a solid tensioner that looks like it will bolt up, but I'm not sure how you would keep it from loosening up.

 

[duramaxzak]

ICT Billet makes a solid tensioner that looks like it will bolt up, but I'm not sure how you would keep it from loosening up.

I'm guessing your talking about this one, I was wondering the same thing if it would work.

 

[JoshH]

Yeah, did the picture I posted not show up for you?

 

[duramaxzak]

Yeah, did the picture I posted not show up for you?

No it didnt

 

[prostreeter600]

I’ve tried different belts etc new tensioner, belt still likes to jump grooves , it’s still on but that’s only after I dialed back the RPMs 3-400 . I have a brand new belt but it’s almost pointless to put it on until I find a solution to keep it in the grooves. The chewed up one I have on there stays on so I’ve just left it on there . So guys what’s the advantages of running this Billet one from ICT ? Is it adjustable ?