What else should be replaced when replacing serpentine belt?

Most importantly, take the tensioner pulley and any idler pulleys (these are pulleys that do not drive anything, like Power Steering) and give them a spin.

How tight should a serpentine belt be on a Jeep Wrangler?

The belt should have about a half an inch of play when at the appropriate tightness. If there is less than a half an inch, the belt will need to be loosened, if there is more, it will need to be tightened.

Why does my serpentine belt keep needing to be replaced?

Worn or damaged Components : If the air-conditioning compressor, the power steering pump, the water pump, or the alternator, driven by the serpentine belt, become faulty, this will affect directly to the belt leading to premature failure.

Why does my serpentine belt keep misaligning?

Turn off the engine and remove the serpentine belt. Shake and spin each pulley to check if there is excessive play or noise. Any play or back-and-forth movement indicates a bad pulley bearing . This leads to misalignment, belt squeaks, and the pulley should be replaced.

Should you replace the idler pulley when replacing a serpentine belt?

We suggest technicians change a pulley whenever a timing belt or serpentine belt is changed and vice versa , but there are eight key warning signs to look out for when a pulley goes bad: Rock – Rock the pulley back and forth. There should be no movement or play from side to side.

How do you break in a new serpentine belt?

The key during this break-in ride is to take it easy and stop frequently. Pull over every few miles and shut off the engine to give your belt time to cool down . Stopping every now and then is a vital part of a proper break-in period. A little patience goes a long way when you're warming up your new drive belt.

Does replacing a serpentine belt improve performance?

Bad Serpentine Belts Cause Vehicle Performance Issues If your serpentine belt is failing, you may notice performance issues with your vehicle. The vehicle may frequently overheat. Your air conditioning or power steering may fail to work or not work properly.

What is a common symptom of a worn serpentine belt?

One of the earliest signs of a failing serpentine belt is a high-pitched squealing or whining noise , especially during engine startup or when turning the steering wheel. This noise is typically caused by the belt slipping on the pulleys due to reduced tension or deterioration.

How do you extend the life of a serpentine belt?

Regular inspection and maintenance, keeping your engine clean, ensuring proper tension and alignment, avoiding exposure to fluids, and investing in a quality belt are all simple yet effective steps in maximizing the lifespan of your serpentine belt.

Should belt and tensioner be replaced together?

When you find a bad tensioner pulley, you have several choices. You can replace only the pulley, or you can buy a new tensioner with a new pulley attached, or you can buy a kit with a new belt, tensioner/pulley, and idler pulley if there is one, and do it all .

What should be replaced with the timing belt?

When you have the timing belt replaced at a reputable service center, the service should also include a few other things. The tensioner and idler rollers should also be replaced. The technician will also inspect the crankshaft seal and the camshaft seal, replacing them if necessary.

What wears out a serpentine belt?

Serpentine belts are designed to last a long time. But eventually, heat and friction will wear them down.

Does your car run better with a new serpentine belt?

Your car's serpentine belt plays an important role in the overall operation of your car, and if it fails, you won't be able to drive normally. In fact, your car will only run for about 20-90 minutes with a broken serpentine belt .

Jeep 4.0L Serpentine Belt Replacement (2024)

Back to "Maintenance"

Please note: This writeup was completed on my 2001 Jeep TJ with a 4.0L I-6 engine, and it also worked on my 1998 Monte Carlo Z34 with a 3.8L V6 (it should also apply to Cherokees, Grand Cherokees and Wranglers with the 4.0L). Although engine layout/design will vary amongst auto-manufacturers, the basic ideas and principles in this writeup should apply to many vehicles with a serpentine belt system.

Every 30,000 miles I replace the serpentine belt in my vehicles whether they look like they need it or not. A serpentine belt is an inexpensive way to make sure that you won't get stranded from a broken, rotten, old serpentine belt. With age, your rubber serpentine belt will begin to crack and dry-rot, and could possibly break at the worst possible place. This belt is also known as the "accessory belt" or "fan belt" and it is a way to transfer power from the rotating crankshaft to drive necessities/accessories such as:

Alternator (for charging the battery and keeping your electrical system running)
Water pump and cooling fan (for vehicles not equipped with an electric cooling fan)
Power steering pump (to give you power-assisted steering if you have it)
Air Conditioning (AC)
smog pump (air pump)
supercharger

On most vehicles that are driven regularly, belt replacement every 30,000 miles is almost TOO frequent. To find out how to check and see if your belt is needing replaced or not, check my belt inspection writeup. When I replace my belt, assuming the old one isn't totally trashed, I put the old one in my trail box just in case a buddy (or heaven forbid ME) needs a spare belt.

This project should take 30 minutes or less, even for the beginning mechanic. Follow along in the easy steps below and you should be just fine.

Addtional notes worth reading:

I have had numerous reports from readers that in 2002 Jeep changed the belt-tensioner square hole size to 1/2". So, you may need a 3/8" or a 1/2" breaker-bar depending on what year your vehicle is.

Tool/Supply List

SAFETY GLASSES!
1 Serpentine Belt (I use Goodyear Gatorback P/N 4060882)
3/8"-drive or 1/2"-drive Breaker-bar/Socket Wrench
Shop Light or Flashlight

Step 1

First, open the hood, get out the shop light and 3/8"-drive breaker-bar/socket-wrench. I suggest using a breaker-bar if you own one; I completely destroyed [read: exploded] a socket wrench doing this one time...the pressure required sometimes is more than what a socket wrench is designed to withstand. Now, locate your "Belt Routing" diagram, which is a decal that should be affixed to the top of the radiator or on the sheet metal under the hood somewhere quite visible.

Step 2

After finding the routing decal, locate belt tensioner. In the picture below, the red arrow is pointing to the belt tensioner's 3/8" square hole for your breaker bar. That silver, oval-shaped metal arm is the tensioner.

Step 3

Now, insert your wrench/bar in the hole pictured in step two. As you are standing at the front of your Jeep facing to the rear, you want to use your wrench/bar to rotate the belt-tensioner arm clockwise (depicted by blue arrow below); this will be towards the ground in most cases. This removes the tension from the belt. While the tension is removed from the belt, pull the belt towards the front of the vehicle (shown by green arrow below) and slip it off of the tensioner. If you have difficulty slipping the belt off of the tensioner, try to slide it off of one of the many other pulleys instead.

Step 4

Now you can release pressure on the tensioner. This step involves completely removing old belt. For my TJ, it involved getting under the Jeep to detangle everything off of the BIG crankshaft pulley and to route then belt around the fan blades.

Step 5

Now that the old belt is off, get out the new belt and put it back on in the reverse way that you took it off, pretty simple! Once you have it put back together, clean up your tools and start your Jeep and listen for any new strange sounds (like a belt slipping or rubbing). Note that a Gatorback belt makes a zippy, whirring sound; don't confuse this with a REAL problem. Close the hood, you're now done.

Page created on 7/14/2003
Last updated on 3/3/2005