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Paccar motor

Dec 06, 2019 at 08:44 PM CST
+ 1

I have a Pete dump truck that has the paccar motor it runs good unloaded but when loaded it don't have no pulling power and take a long time to get up to speed

Replied on Sat, Dec 07, 2019 at 07:07 PM CST

Take to Peterbilt and get motor looked at,(diagnose done) get torge checked. Before doing that change out fuel filters.

Replied on Sat, Dec 07, 2019 at 07:07 PM CST
- 1

I heard that paccar buy out the ideas and designs from cat. I had a 579 Pete with 450 paccar . 80000lbs all over country never weak motor. Did 181,000s in 10mts. Would buy another in heartbeat. 8.8 mph loaded. 10.5 mty.

Replied on Sun, Dec 08, 2019 at 01:16 PM CST

The paccar motor I have is a good motor as far as longevity. Maybe you need more hp and most of all a proper back axle ratio. Like the 325 gear is for highway only and faster speeds. 325 is a tall gear. Take to much hp to move it. A 355 is a good ratio to have for pulling and of course your torque has to be 1850 to 2200 lbs of pulling power. So big clutch. Big drive line. Big torque. Most of the paccar motors seem to be set up for freighters, not pulling.

Replied on Sun, Dec 08, 2019 at 03:18 PM CST
Originally Posted by: ROBERT YOUNG
Quote: "The paccar motor I have is a good motor as far as longevity. Maybe you need more hp and most of all a proper back axle ratio. Like the 325 gear is for highway only and faster speeds. 325 is a tall gear. Take to much hp to move it. A 355 is a good ratio to have for pulling and of course your torque has to be 1850 to 2200 lbs of pulling power. So big clutch. Big drive line. Big torque. Most of the paccar motors seem to be set up for freighters, not pulling. "

You hit the nail on the head, the new trend is super tall gears, 3.08 and even 2.64! A 3.55 or 3.73 works great, less work for the engine to perform and easier to get out of a soft field.

My new truck is a paccar, next one will be too, I believe 1850 is the max stock torque, and it makes it way down low, it's been an odd feeling for me to run the engine down at say 1200 rpm, but it stays there pretty well and with the various controls the pyro stays down around 650-680 degrees.

Replied on Mon, Dec 09, 2019 at 06:00 AM CST
Not a fan of paccar motor for otr. Not enough people to work on it or parts available. Might be good regional.

Art Pfluger
Replied on Wed, Dec 11, 2019 at 02:09 PM CST
+ 1

Could be many reasons so keep it simple first. Do you have a boost gauge? what is your max boost pressure with a load? check for leaks in charge air system- park brake on set fast idle to around 1300 and check around boots for leaks and listen for whistling also around cooler. Fuel filters like someone said and air filters, also take intake manifold sensor off and clean it if all sooted up, buy a new one if many miles on it. any ay start there.

Replied on Wed, Dec 11, 2019 at 08:54 PM CST
I haven’t been a great fan of paccar. But I do live the fuel mileage. This truck I’m running now actually has decent power. The only problem is if you want to get them turned up you have to pay the company paccar for it. Then you have to pay the mechanic shop. And to find parts you have to get from Peterbuilt on most of them.