JoeH

Location?

Clogged fuel filter still let's you hit good boost numbers, up until a continually decreasing rpm as the filter becomes more and more clogged. Basically acts like a governor.

And when did you last change your fuel filters?

Dual stacks look killer on R models.

Vapor barrier under the concrete only prevents ground moisture from soaking up through the slab. It doesn't prevent condensation from forming on a cold floor with warm humid air above it. I wouldn't do any less that 6". If there are parts of the garage that won't/can't have trucks parked on them (shelving/tool areas/etc) you can do one layer of rebar in the middle to save $. For truck lanes/parking areas I'd do the rebar at the 2 and 4 inch depths in the concrete. Metal closer than 2 inches to the surface of the concrete can rust & pop the concrete off. You see this on older bridge underpasses frequently.

How finely crushed are we talking about? 6 inch chunks or 1 inch gravel sized? Or a mixture? Larger chunks could create pressure points, as they don't readily give way to movement like gravel does.

To that point I delivered concrete to a house years ago. Plumbers had to trench the septic out through the existing garage, so they cut a 1 ft wide strip out of the garage floor. The entire garage floor was floating 6 inches!! The dirt had settled away from the slab, leaving the whole garage floor floating! Homeowner was an older gentleman, had been parking his car in there for years. His response? "This'll be the next homeowners problem, not mine!" They finished the septic repair and filled in the trench, leaving the rest of the floor floating!

Interesting! I laugh at "zero emissions". You don't get movement without forcing energy from something. That something will always produce a biproduct, whether it's coal's co2 and ash, or nuclear waste. Then you have the batteries to dispose of, which will likely mostly be recyclable... Waste collection is a good test track for electric trucks. It does make sense for such a localized use, but I wonder how well they will hold up? Maybe they'll glitch out like Toyotas Prius and just accelerate and the driver can't stop? That'd be awfully destructive at 70,000 lbs with 4,000 lbs of torque!! That sucker will keep going till it encounters enough resistance that the tires just sit there spinning on blacktop!

Higher PSI also means more brittle, less forgiving to slab flexing. But again, sub grade prep and rebar are King. What concrete can hold on one square inch dirt can only hold on one square foot. (Give or take). Steel rebar and slab thickness help to disperse point loads (i.e. bottle jacks) across a larger footprint underneath the slab. Worth looking at concrete load flex diagrams to understand how concrete is stressed. When a load is put on the slab, the top half of the slab will be in horizontal compression and the lower half will be in horizontal tension. Having rebar in the top and bottom halves of the slab would make a 3000 PSI slab good enough. Concrete has a lot of compressive strength, but not much tensile strength. The rebar in the lower half is what gives the slab tensile strength during flex to prevent cracking.

Ivanuke is in Houston I believe. It doesn't get cold enough there to justify in-slab heat. I would not do Type III "high early" cement. It'll shorten how long the crew has for working with it. Type I cement will be hard enough in a week to roll trucks across.

Looks like they tried chiseling out the rust, gave up and hammered the outer rail down to get it to close up.

Gotcha, thought you said 2 gunite companies and 4 concrete companies. Gunite trucks looks similar to meter mix trucks, but they produce different products. Not sure how far barrel truck chutes reach. My meter mix truck can reach 18.5 ft straight off the back of the truck. A barrel should be able to reach a bit further. If you break the pour lengthways in half you should be able to reach in 25 ft from either side to cover the 50 ft, assuming the truck can get his tires right up to your forms without hitting any form braces. You may consider using a "screed key" down the length in the middle (along that 25 ft line)to prevent a cold seam and to keep the two halves from being able to shift vertically from each other. Screed keys notch the face of the concrete with an indent that will get filled by a slab being poured against it. It effectively locks the two slabs together so they can't shift vertically. Google should give you pictures of them.

Are two of the concrete plants volumetric mixers? My dad and I own meter mix trucks, personally I'm partial to them. But you want a reputable company with good drivers! Meter mix drivers can't just be drivers, they have to know what good concrete looks like and care enough about their career to want make the best concrete they can for every job! Barrel trucks, drivers don't have to know anything about concrete, but the company as a whole has to be reputable and use quality materials.

Will you be hiring a concrete finisher? Unless you have a crew that knows what they're doing I strongly recommend having an experienced crew on hand to screed, float, and power trowel the surface. You want your floor flat and smooth and durable. 1 cubic ft of concrete weighs about 146 lbs. That's a lot of weight and material for an inexperienced/out of shape crew to handle under the pressure of barrel truckloads getting hot. Consult with them on truck access/reach to decide if you need to rent a concrete pump or if the trucks can reach and unload without a pump.

And it pays to have the right tools for the job!

If you are using barrel trucks your contractor should specify how much time between truck loads showing up. If the trucks are loaded and dispatched all at once, the first load will be nice, the second will be harder to work with, and the third will be a ball buster. They should be loaded and dispatched at a frequency that the contractor can handle. Otherwise they will add water to subsequent loads to try and maintain workability, and your floor's integrity will suffer. Every time I drive through new neighborhoods I can see where the crew took too long to unload a truck and they added water, causing the last concrete out of the truck to be visibly inferior to the first concrete out.

It really comes down to good subgrade prep. Up north we have to do a good subgrade of stone because as the ground freezes and thaws the slab needs a "cloud" to float on so that there aren't any pressure points against the underside of the slab. A good base of gravel acts like a mattress to allow the slab to not break during ground movements. In Texas you won't get the freeze thaw cycles we get that are very destructive. I would guess 6-8 inches would be adequate. Rebar on 1ft grid is a great idea, you want it in the middle of the slab depth. I don't care for fiber, I've been told it actually weakens the concrete's actual strength, but I haven't done my research on it. Pour it during cooler temperatures, 60-70 degrees Fahrenheit. Don't pour it wet. A 3.5 inch slump should be workable for a skilled crew if you are pouring a minimum of 6". If they need more workability than that then order the concrete with a mid grade plasticizer. Water is the #1 killer of concrete. It is a catalyst that causes the cement powder to crystalize, thus glueing everything together. The water will leave, and if there is a lot in it you will get shrinkage cracks, you can get spalling, dusting, etc. Plus your floor will not be as dense. 3500 psi is adequate, but 4000 psi will give you a higher cement content that will prolong the durability of the surface. The PSI rating indicates how much weight the concrete can hold before failing. (After a standard 28 day cure).

That was a 283 HP motor not a 237. Glad you were able to sell it!

Superliners make Mack junkies drool. Put pictures up regardless of whether or not you want to sell it.

My 95 isn't vmac it's completely mechanical.

If you're running into problems getting parts for that engine like us with our 2 valve '79, you can always repower it with a mechanical e7 motor, or pick up a parts motor. E7 will likely bolt right in, but I'd ask around here first. If you don't have an air ride cab, you can add that assuming your hood mounts on the firewall are rollers and your radiator support arms come off the frame instead of the firewall. We just put a junk yard Mack's cab air ride onto a 1988 we bought. You wouldn't believe how nice air ride is on a cab. You'll kick yourself for not doing it sooner.

Why would you sell it? Are you upgrading? If you are, you're going to get yourself into an expensive payment for a truck that goes to the dealer more times every year than your '86 did in it's lifetime. Meanwhile, someone else is going to be riding around making fat stacks with your old truck and you will be pining for your old truck, kicking yourself for selling it. If it has severe rust jacking in the double frame, you should take that seriously and consider fixes. We bought a '95 RD that we had to remove the dump body and we took one side of the frame apart at a time to clean out the rust and sand blast and paint. Only real cost to us was about $1000 in new frame bolts and a cracked crossmember. But we have the tools. You may also be able to buy new rails from Mack, but that will likely cost you close to 20k after freight for all 4 rails.

'95 rd688s with an 8LL

Honestly I'd put the dump body up and kneel on the floor between the frame and driveshaft and do it from the back of the trans. But I'm also 6 ft and a buck fifty soaking wet. I fit where others don't. Obviously block the dump body so it can't drift down on you.

Interesting to read about the resonant ride... Might explain that weird flutter my 95 e7-350 does around 1200 when I'm maintaining speed with minimal power application. Almost to 20,000 hours.