Need some advice on buying a Semi

I thought about renting but I think $500 a pop is going to add up quick with practicing and especially if I have to take the test more than once. I know my one neighbor has some trucks for his construction business, but they are usually gone. He's got a few dumps I could probably use to get a Class B, but I'd rather have the whole enchilada.


Out here that $500 gets you a day of practice and a day testing. The trucks they have you test in are single rear axle trucks with synchronized six speeds and a 18' bumper pull car hauler trailer; the minimum you need to get a class A but also extremely easy to drive. The company I know of does two free retests but usually people don't need them.


The pre-trip inspection was the only moderately difficult part for me, but a buddy gave me a script that the trucking school gave him to memorize. If you want I can scan it and send a copy your way to study.
 
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The only problems I have heard with any C15 are the ACERTs.




the company I drive for has 5 ACERTs and none of them give us any trouble.


I've had nothing but issues with the 3 cats I've owned , I went to an N-14 select turned up to 550 and it will out pull all of my cats and get better economy and is 10x more reliable than my cats were , ill never own another cat
You had some sick kitties then, my truck leaves N-14's wondering wtf just blew their doors off. Haha
 
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I'm a huge cat fan, out here in the west with all the big hills and mountain grades, cat and cummapart dominate, you couldn't give me another ISX after running an acert cat, but since you're not lookin to go that new its pointless to school you on those.

The big cam III and big cam IV are good engines that are easy to get power out of, and if you happen to stumble across a 444 Cummins......jump on it, they're a powerhouse right out of the gate, but super rare to find.

The N-14 is about as reliable as they come, especially if you get a later celect plus, those can be factory set to 525hp and still get good mileage.

The B model cat is another good one that's easy to get good power out of, where the Cummins is a higher RPM engine, the cat doesn't like to go much past 15-1600rpm. One thing I've heard with a B is that if you go much past 550hp they tend to be less reliable. Stay away from the PEEC cat engines, the electronics on those are a total pain in the ass.
The E model is a good one as long as you get a 475/550 one, the engine ID tag on the front driver side valve cover will tell you what its got.

And the Detroits...... the series 60 is another favorite of mine, decent power but great fuel mileage and reliability.
Don't rule out a silver 8V92 if you happen to run across one, yeah theure noisy and dirty, but theyre easy to get big power out of
 
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I think pretty much anything will be good for what your looking for, as long as it is mechanically sound, the rubber is good, and it will pass inspection with minimal work.

If you decided to keep it, that KW will make a nice Sunday drive/ play toy.
 
Out here that $500 gets you a day of practice and a day testing. The trucks they have you test in are single rear axle trucks with synchronized six speeds and a 18' bumper pull car hauler trailer; the minimum you need to get a class A but also extremely easy to drive. The company I know of does two free retests but usually people don't need them.


The pre-trip inspection was the only moderately difficult part for me, but a buddy gave me a script that the trucking school gave him to memorize. If you want I can scan it and send a copy your way to study.

Or find a pintle trailer and take your test for class A. I used a single axle dump and a pintle hitch trailer to get my class A.


I'll be calling the local company a few people I know have rented trucks from to get a price. It certainly won't come with a day of testing. My buddy rented a truck from this place and it failed the pre trip because the front axle had a large crack in it. The same buddy wanted to use his dump and a pintle trailer to get a CDL A and the MVD examiner said he wouldn't sign off on the endorsement unless it was a 5th wheel. There seems to be a conflict of interest in my opinion because the examiner for the MVD is the same guy who does the instruction for the community college. After failing my buddy he tried selling him on the course he instructs... "People who don't take my class don't pass the driving exam".

I'm gonna see if I can take the exam in a different county...


I'm a huge cat fan, out here in the west with all the big hills and mountain grades, cat and cummapart dominate, you couldn't give me another ISX after running an acert cat, but since you're not lookin to go that new its pointless to school you on those.

The big cam III and big cam IV are good engines that are easy to get power out of, and if you happen to stumble across a 444 Cummins......jump on it, they're a powerhouse right out of the gate, but super rare to find.

The N-14 is about as reliable as they come, especially if you get a later celect plus, those can be factory set to 525hp and still get good mileage.

The B model cat is another good one that's easy to get good power out of, where the Cummins is a higher RPM engine, the cat doesn't like to go much past 15-1600rpm. One thing I've heard with a B is that if you go much past 550hp they tend to be less reliable. Stay away from the PEEC cat engines, the electronics on those are a total pain in the ass.
The E model is a good one as long as you get a 475/550 one, the engine ID tag on the front driver side valve cover will tell you what its got.

And the Detroits...... the series 60 is another favorite of mine, decent power but great fuel mileage and reliability.
Don't rule out a silver 8V92 if you happen to run across one, yeah theure noisy and dirty, but theyre easy to get big power out of

Excellent information, I'll take as much of that technical stuff as I can. I get stuck reading alot more opinion than fact on big motors from google searches. Most people just push whatever they own. I didn't know about the 3406 being more of a low RPM motor vs the 855 being higher. Is that simply a displacement thing or ?? I'm impartial between CAT, Cummins, and Detroit, I just want something that's reliable, I can work on when if it does break and that I won't loose my ass on for parts if it does.

While I've got you here what are the limits of the motors I can afford? Like early Dmax rods are on borrowed time after 500rwhp. So where do things go grey in the 855, 3406B, and 8v92? What does it take to get them there? I saw that larger injectors for a 8v92 are pretty cheap compared to something like an E series CAT.

Speaking of the 8v92, most I read about two stroke Detroits is that they are gutless, gotta be revv'ed to move a load, and are fuel sluts. I've read a few good things about the Silver 8v92, but the rest of the rumor worries me.

Also any info on transmissions or rears? I don't read much about these, but I have stumbled into a little info about general gear selection vs usage/load size.


I think pretty much anything will be good for what your looking for, as long as it is mechanically sound, the rubber is good, and it will pass inspection with minimal work.

If you decided to keep it, that KW will make a nice Sunday drive/ play toy.

I'm already working on my pre-trip/inspection stuff so when I go check out a truck I can keep an eye out for problems and potential investments/money pits.

I found a second local W900, a 1989 model, it looks real sharp, but I haven't heard back from the number on the listing. It's in better condition outside than the blue 1984 and the guy is asking $6500 OBO. But I have no other details on it at this time. I'll be calling again today since it looks like a pretty good deal.
 
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Excellent information, I'll take as much of that technical stuff as I can. I get stuck reading alot more opinion than fact on big motors from google searches. Most people just push whatever they own. I didn't know about the 3406 being more of a low RPM motor vs the 855 being higher. Is that simply a displacement thing or ?? I'm impartial between CAT, Cummins, and Detroit, I just want something that's reliable, I can work on when if it does break and that I won't loose my ass on for parts if it does.

Since the dawn of time cats have been a low rpm engine and Cummins has been liked about 4-500. More rpm, its just the way they're designed/built

While I've got you here what are the limits of the motors I can afford? Like early Dmax rods are on borrowed time after 500rwhp. So where do things go grey in the 855, 3406B, and 8v92? What does it take to get them there? I saw that larger injectors for a 8v92 are pretty cheap compared to something like an E series CAT.

I'm not really sure on that, I know the DDEC equipped 8V92TT's can go to 750hp in marine applications. I've heard stories of big cam engines going almost that high and being alright but I don't know that for an absolute fact. As far as cats go, like I said earlier, I've heard 550hp in B model is about all you want to go, I'm not sure if that's because they get hot too quickly or if its something else, maybe smokinCAT or JFaulkner would know more.

Speaking of the 8v92, most I read about two stroke Detroits is that they are gutless, gotta be revv'ed to move a load, and are fuel sluts. I've read a few good things about the Silver 8v92, but the rest of the rumor worries me.
As I recall they do get thirsty when you start throwing power at them, but as far as being gutless, I pulled a dump bed off of a 1989 W900L with a silver 8V92T and put a 5th wheel plate and a pusher on it and used it for an equipment transport truck, it pulled dead even with our other heavy haul truck that was a 525hp celect plus Cummins.

Also any info on transmissions or rears? I don't read much about these, but I have stumbled into a little info about general gear selection vs usage/load size.
Depends on what you're going to be doing with the truck, my personal choice would be an 18 speed, 3.55 rears, and lo-pro 22.5's
 
Low pro 22.5's?! Depending on what your gonna do I say low pro 24's or maybe tall 24's.

I think on a bmodel anything over 600-650 starts to shorten its lifespan from what I've read but my minds kinda scattered right now.
 
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The B's big end bearings are small compared to a C or an E. The hot trick is to put a C crank and rods in. If you crank on it just plan on spinning a new set of bearings in every 250k or so. I don't know about low rpm's, anything below 15-1600 and mine starts to get hot. With the tighter governor spring it'll pull to 2200 but I usually don't spin it over 2000.

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Mine gets warm below about 1350-1450... It will pull to I know 2000 maybe more but I try and keep it to about 1800.
 
Low pro 22.5's?! Depending on what your gonna do I say low pro 24's or maybe tall 24's.

I think on a bmodel anything over 600-650 starts to shorten its lifespan from what I've read but my minds kinda scattered right now.

We run low pro 22.5's on all our trucks. If you need the ground clearance then 24's are fine, but those are HEAVY tires
 
We run low pro 22.5's on all our trucks. If you need the ground clearance then 24's are fine, but those are HEAVY tires

True... I figured with a local truck that wasn't going OTR, little ground clearance might be nice.
A highway truck in my opinion... The lower the better.
 
Heavy tires make no sense for us because our loads are billed based on net weight, so the lighter we are, the more we can haul and the more money our company makes. I like my paychecks to go through so I haul as much as I can and still be legal, which is 70-75,000 pounds depending on where I'm at and where im going
 
Heavy tires make no sense for us because our loads are billed based on net weight, so the lighter we are, the more we can haul and the more money our company makes. I like my paychecks to go through so I haul as much as I can and still be legal, which is 70-75,000 pounds depending on where I'm at and where im going

Completely understandable!

Just like I'm super heavy in my opinion for empty...
 
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The B's big end bearings are small compared to a C or an E. The hot trick is to put a C crank and rods in. If you crank on it just plan on spinning a new set of bearings in every 250k or so. I don't know about low rpm's, anything below 15-1600 and mine starts to get hot. With the tighter governor spring it'll pull to 2200 but I usually don't spin it over 2000.

Sent from my DROID RAZR HD using Xparent BlueTapatalk 2

A lot of the bearing issues with the narrow bearing B model was the bearing itself, I have heard more than one person say that the bearing tech has gotten a lot better, and while the bearing is narrower the crank journal it spins on is a larger diameter, the C/E have a wider bearing but the diameter of the journal is smaller, and the acert combines the two give the best of both.

I have been doing some research lately and there are factory 1900hp V12s that are running the same bearing as the early B, so half that is 950 so I think a narrow journal B will be just fine these days.

I think you could cool yours off a little by advancing the timing.
 
Peterbilts are heavy, at least the 379s are, Id say the classic xl we have is a couple thousand pounds lighter than what you are running right now and it is a condo sleeper.

Granted, my trailer is heavy as all get out being all steel and such.

Who was the cooling things off comment made to me?
 
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