when to replace fan belts

Let's see - I have a 1999 (bought new in July of 1999 - National RV Tropical with tag axle) chassis v10 with a 129000+ miles & 14 + years old. I am still running all the original hoses and the serpentine belt. I carry spares and I check them regularly (as recently as 4 months ago) and unbelievably they all still look and feel excellent. I am sure they will fail eventually but we do not travel nearly as much as we used to (maybe 7000 - 8000 miles a year) and unless I see that they do not look right when inspecting I am leaving them alone. I'm thinking they may last until I quit RVing, ha. By the way I did have the plugs changed around 94000 miles just because that was not something I wanted to have to do on an unplanned basis, but the engine was running just fine at the time. I believe that this particular RV by National had the cooling air flow around the engine, either accidentally or by design, dialed in about as good as it can get. Other than the plugs and routine lubrication this engine has required zero maintenance.

Inspect for cracks if none continue on. If you are concerned change it and keep as spare. I change hoses and belts at 100k on my vehicles, I usually keep them a long time, and have had to reuse old hoses due to failure of newer hoses. I was on I -10 Crossing the Achafalya and had a hose failure and a belt failure soon there after within 3 days of each other in a van I had. Both were fairly new, used old ones to get out of a bind. Now that I am older and have an RV carrying spares is just safer or smarter these days.

falconbrother wrote:
I wouldn't even think about those belts yet.

x2. You can inspect them for free. No need to replace if there is no sign of wear. As to the poster whose alternator seized causing the belt to break, that can happen to a new belt.

I would have a spare. Change belt in good weather not 40 mph winds in a thunderstorm beside the interstate on a blind corner.

bass n bob,
In all reality, if you think about it, belts have a seriously hard life. Eighty gazillion turns while the engine is running, heat, cold, dirt, debris, and more, as cheap as they are, I wouldn't even hesitate at the 30K mile point. Many rigs, especially the front engine models (gas) are actually quite easy to change it. Many times, almost no tools are needed due to the fact that the belt is held with a tensioner. And that tensioner only needs usually a 1/2" breaker bar or 1/2" ratchet to tweak to release tension and the belt falls off.

One thing you, or anyone does NOT want to do is, change it in the middle of the desert or, some desolate place, possibly at night (if you drive at night), in the rain, or any other less-than-perfect set of conditions due to trying to stretch more miles out of it. I know I wouldn't.

Scott

I wouldn't change it yet. Check it out, get a new spare, have the tools needed and enjoy life. Gates belt tools Ford serpentine belt routing

I wouldn't even think about those belts yet.

actually there is a belt routing chart on the cover of the Ford manual.

For the belt discussion regardless if you change or not, either find a belt routing chart or make one yourself, before you take the belt off or before it breaks. Without a routing chart, the belt is hard to route properly. I have a 8.1 chevy and there was no routing chart anywhere near the engine compartment or in the manual, so I got underneath and drew one for reference. just as a side note my 2004 workhorse 8.1 chevy web site says belt is good for 150,000 miles on the original belt, but a visual inspection that shows small cracks on the ribbed side of the belt would indicate "time to change" in my opinion. Find or make that chart NOW before you need it.

Chev belt routing

Although the OP is asking about Ford, I included the chev picture of a belt routing in the above link.

DUNEBUGGYDOUG wrote:
For you to have piece ofmind , go ahead and change it.Keep old one in storage compartment for spare

BINGO! New now...keep old as a spare