When to Change Belt Tensioner and Pulleys?

Gates all the way. Earlier on this thread there was pictures of the new and Improved Freightliner version.... it’s the the Tensioner Gates designed for the DD series. I’m assuming it’s just re-boxed.

The OEM French built tensioner looked like the coolest new technology... but there was to many things to go wrong, (locked up shock/tensioner, minute wear causing miss alignment, etc) Since we’ve changed the fleet to the Gates version tensioner and belts, we have very minimal issues. It’s hard to beat technology that’s been around for decades.....

 

Update—

I replaced my belt tensioner about 6 months ago. I will say that even if the belt tensioner can go over 500k miles, I’m not so sure it’s a good idea to wait that long. My new belt tensioner held my belts on much more tightly than my old one. Perhaps the best thing to do is to use a belt tension tester like the Krikit, and that will help determine how much more life there is in the belt tensioner.

 

The other side of this coin that no one has mentioned is a loose tensioner or worn out belt will allow excessive slippage (even if it can’t be heard. Slippage (even from a rubber belt) will wear the Iron off every pulley. Let alone reduce the efficiency of all that it drives ( alternator, A/C, etc.)

Keep it maintained of be ready to replace it all.

 

I notice the tensioner has different pulleys on my new 2020 Detroit than the 2013 had.

My 13 had flat (or smooth faced) pulleys that the belt rode on. The 2020 has ribbed pulleys.

I'm thinking this should help with the uneven face wearing and the belt walking off..

 

I would like to see what’s new on the DD’s. Post a pic if you would get a chance???

The early version tensioner also had two smooth and 2 grooves pulleys, so now my interest is spiked.

 

Thanks

 

I'll try and get a pic during the day when it's light out.

 

I just change mine annually, which is about 155k that way billy bobs bend ya over road service doesn’t get my money. Keep the old belts and tensioner and idlers in truck for spares.

 

what does it mean when a belt looks like it's cut in from the top, scooped out in some spots but rib still there, other spots edge rib clean sliced off. new front cover had the shop take off and put back on tensioner and vibration damper, the only place you can't see where something could be rubbing is under vibration damper tucked into motor mount

 

That used to happen to mine when it was out of alignment and jumped the pulley. Usually but not always jumping off.Ive even used a 6 rib belt instead of an 8 rib, centered, to catch it when it jumps a rib on the pulley. I replaced my front covers and damper recently. So far at 50k miles. No more problems. If everything’s lined up right, you shouldn’t be having that problem. You’d think they replaced the belt. Aside from a tensioner going bad, can’t imagine what caused it. I would buy 2 belts. An 8 rib, and a 6 rib. Run the 6 rib centered, see if it jumps the grooves. If not, throw the 8 rib on and keep the 6 rib as a spare. Good for a spare, especially if belt failure is from a misalignment. Get you to the Dealer for the right parts, A new tensioner, keeping the old one as a spare, isn’t a bad idea either. That’s what I’ve always done anyway. Along with any short belts needed to run alternator in a jam, should another accessory like a/c lock up.