What are the pros & cons to the 3126 Cat engine in expediting?
Cat 3126
- Thread starter GaTrucker05
- Start date
No comments good,bad or ugly.
Murraycroexp
Veteran Expediter
I don't remember. I remember having trouble with the 3116s but not the 3126. Maybe the improvements helped.
Pretty durable engine overall. If older, they may be a ggod candidate for a rebuild or maybe not. They are a sleeveless block so a rebuild depends on a block that can be machined for the new cylinders. Most are good if no damage.
Engine runs well at high RPM's and is used quite a bit in construction and marine applications.
Engine runs well at high RPM's and is used quite a bit in construction and marine applications.
Deville
Not a Member
I like mine. I've had 3 3126 motors, this one is a 2000 & it's been the best one to date. 555,000 on it & it's still going strong. I think I need to change my wire harness as i'm noticeing a little issue lately.
The truck needs Valve adjustments every 75000 to 100,000 miles. Change the oil every 5000, to 8000 miles is a must as they get older. Run some type of fuel injector cleaner though it on a regular basis.
The cold startup & warm up for mine makes a big diffrence. At this trucks advanced years & mileage it's deveolped a miss when it's first started up in the morning & it can take up to a half hour depending on the weather before it smoothes out. I always let it warm up before I go.
They say if a CAT motor isn't leaking than somthing is wrong. Well mine doesn't leak because I fixed all the leaks & it runs fine.
I've dumped alot of money in to this truck & maybe 20% of it has been engine related.
It pulls good enough on the hwy, top speed on mine the way it's geared is about 68-70 mph which is fast enough. It's ok on hills with up to 5000 pounds or so before I need to shift most of the time. When it's loaded to capacity I could be in 4th gear & barely pulling the hill at 25 mph.
The best years for this motor where 98 though 2002. After 02' they made changes to the motor that caused a lot of realibility issues. I think they were resloved by 2005, than CAT discontiuned the motor by 2007.
The truck needs Valve adjustments every 75000 to 100,000 miles. Change the oil every 5000, to 8000 miles is a must as they get older. Run some type of fuel injector cleaner though it on a regular basis.
The cold startup & warm up for mine makes a big diffrence. At this trucks advanced years & mileage it's deveolped a miss when it's first started up in the morning & it can take up to a half hour depending on the weather before it smoothes out. I always let it warm up before I go.
They say if a CAT motor isn't leaking than somthing is wrong. Well mine doesn't leak because I fixed all the leaks & it runs fine.
I've dumped alot of money in to this truck & maybe 20% of it has been engine related.
It pulls good enough on the hwy, top speed on mine the way it's geared is about 68-70 mph which is fast enough. It's ok on hills with up to 5000 pounds or so before I need to shift most of the time. When it's loaded to capacity I could be in 4th gear & barely pulling the hill at 25 mph.
The best years for this motor where 98 though 2002. After 02' they made changes to the motor that caused a lot of realibility issues. I think they were resloved by 2005, than CAT discontiuned the motor by 2007.
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I have a 98 3126 and its been ok. To me it runs way too hotfor my liking.....I'm thinking about putting a 4 row radiator in it to see if that helps. Other than that....with decent maintenance its never really given me too many issues. Mine has around 350,000 miles (reman).
I do think its better at lower speeds seems to me to fall a little flat at highway speeds. I run right around 70mph with 3.73 rears and a 10 speed direct.
I do think its better at lower speeds seems to me to fall a little flat at highway speeds. I run right around 70mph with 3.73 rears and a 10 speed direct.
Deville
Not a Member
Wow even with that gearing u think it runs flat with a 10 spd? That's cray yo! I'm running 4.11's & 6 spd. My top speed in 67-68 mph. Under the right conditions I can do 70.
Deville
Not a Member
How was ur fuel economy running at 65 mph? I avg about 10 mpg.
jeffman164
Seasoned Expediter
760,000 miles and burns absolutely no oil whatsoever . Who woulda thunk that .
Deville
Not a Member
555,000 Mine burns very little as well.
jeffman164
Seasoned Expediter
Forgot to mention , just had an oil analysis done with excellent results !! YIPPEE I O TY EEE !!
You can add a after cooler or go to a lower thermostat. May have the wrong one in it.
Seems like my fan runs all the time now,very noisy.It use to only come on when it needed too doesn't run hot but that noise is ruff.Any ideas what to do maybe change fan clutch.Anyone else got this problem?
Fan clutch and possibly the fan itself if it is a nylon/plastic one instead of metal.