Concrete mixer truck dimensions, measured: ten machines and the door they have to clear

Ten of the sixteen self-loading concrete mixers in our product record carry a measured overall length, width and height. Listed by discharge capacity, in metres, length by width by height: 1.0 m³ — 4.35 × 1.60 × 2.45; 1.3 m³ — 4.95 × 1.65 × 2.75; 1.5 m³ — 4.95 × 1.80 × 2.80; 1.6–1.8 m³ — 7.06 × 2.21 × 2.58; 2.0 m³ — 5.00 × 1.85 × 2.80; 2.4 m³ — 5.10 × 1.95 × 2.80; 2.5 m³ — 5.30 × 2.10 × 2.80; two 3.0 m³ machines, both 5.30 × 2.15 × 2.85; and 3.5 m³ — 5.45 × 2.30 × 2.90. Eight of the ten have no published model name, so all ten are identified here by discharge capacity, which is the only label in the record that means anything to a buyer. The 1.6–1.8 m³ machine is the one published here as the SLM-18.

Every machine in that list is a self-loading mixer. It drives to the aggregate, loads itself with its own bucket and mixes on the move. It is not a truck-mounted transit mixer charged at a batching plant, and these figures do not transfer to one. Read as a set, the ten sit inside a band 700 mm wide and 450 mm tall. Length is the dimension that does not behave: it runs from 4.35 m to 7.06 m, and the longest machine is not the largest. The 1.6–1.8 m³ machine is 7.06 m, which is 1.61 m longer than the 3.5 m³ machine at 5.45 m. It comes from a different supply line and steers by articulating at the middle of the chassis. So if what limits your site is the lane, the gate or the yard rather than the pour, capacity will not tell you whether the machine gets in. The measured triple will.

Nine of the ten rows carry one overall-dimensions figure supplied by the plant, with nothing stating whether the machine was standing in travel position or with its loading bucket raised. That is recorded as unverified rather than assumed, and it is on the written list of things to confirm before a drawing is accepted. Width is barely affected by the difference, so those figures stand. Height is affected, and for those nine it is a height of unstated posture rather than a travelling height. One of the nine is already published as a model on this site with its dimensions shown, and the same caveat belongs on that page. The tenth row is different. It was read off two general-arrangement drawings, one English and one Chinese, whose figures agreed number for number, and those drawings set the travel-position body height out separately from the bucket-raised overall height.

One row is thinner than it looks. Of the two 3.0 m³ entries, the eight-wheel-drive one carries its dimensions and its discharge figure and almost nothing else: the source table was misaligned on that line, so cab, engine, transmission, axles and tyres are all missing from it and are recorded as still to be obtained. The dimensions are published because the table gave them. The rest is not filled in from the machine sitting next to it in the same list, even though that machine shares the identical 5.30 × 2.15 × 2.85 m triple. Two rows with the same dimensions, one recorded as eight-wheel drive and the other with no drive configuration recorded at all, are an ordinary thing to find in a range. A row completed by inference is not, and it is not recoverable later, because nothing in the finished document says which parts of it were guessed.

On the one machine where both postures are documented, the difference is 870 mm. The SLM-18 drives at 2.58 m; its bucket reaches 3.45 m at full lift. That gap is the reason a single unlabelled height cannot be planned against — 870 mm is the difference between a machine that clears a site entrance and one that stops in it. For the contractor it is two separate clearances rather than one. The height the machine drives at governs the gate, the archway, the ramp into a basement car park and the cable strung across the lane. The height it loads at governs what is above the aggregate pile, because the bucket has to come up there and nowhere else. A yard can pass the first test and fail the second, and nine of the ten rows above give one height without saying which of the two it is.

The opening that decides is 2.29 m wide by 2.535 m high. A 40 ft high cube measures 2.698 m inside, but its door opening is 2.585 m, and taking 0.05 m off each critical dimension as the margin a loading crew works to leaves that usable figure. Width is checked before height, because the walls of a box do not come off and a width failure has no answer, while an over-height machine can sometimes be loaded from above through an open top. That test is argued out model by model in the container guide on this site, together with the reason an ordinary box is tighter still, and it is not repeated here. What this page adds is the same arithmetic run across all ten of the measured machines, which is a wider set than the published range.

One of the ten clears both tests: the 1.0 m³ machine, 1.60 m wide and 2.45 m high, with 690 mm of width and 85 mm of height in hand. Eight pass on width and fail on height — by 45 mm on the 1.6–1.8 m³ machine, and by between 215 mm and 315 mm on the other seven. The 3.5 m³ machine fails both, 10 mm over the usable width and 365 mm over the usable height. Those are computed clearances, not booking verdicts. On the nine rows whose posture is unstated, a lower travel-position height would change some of the height answers, and that is a question for the plant and not for a spreadsheet. Until it is answered they are quoted out of gauge — flat rack, open top or roll-on/roll-off — and the mode goes into the quotation before a price is agreed.

Do not carry a dimension off this page onto a model that has none. Four of the six mixer models published on this site have no dimensioned drawing in our hands, and their dimensions are recorded unverified. One of those four carries a discharge rating that also appears in the table above, at 2.4 m³, and the published model and the measured row are different machines from different supply lines, sharing a rating and nothing else. A second has no settled rating at all: its English and Chinese specification sheets disagree, so no discharge figure for it is published here. Capacity is a rating, not an identity. The two supply lines in this record differ by 2.11 m in length at close to the same output — 7.06 m at 1.6–1.8 m³ against 4.95 m at 1.5 m³. A machine without measured dimensions shows none on its model page, and stays quoted out of gauge until a drawing arrives.

One of the sixteen mixers has a wheelbase and a track width in the record: 2,330 mm and 1,600 mm, both on the SLM-18's general-arrangement drawings. Every other mixer row has neither. Every other track width we hold sits on a drawing bound to no model, apart from one pair that contradicts itself — two versions of the same drawing print 1,960 mm and 1,760 mm. That is logged as an open conflict rather than averaged into a number that would look exactly as solid as a measured one. No turning radius exists for any of the sixteen mixers either, and one cannot be derived from a wheelbase on a machine that steers by bending in the middle. If the job is a courtyard, a dead-end lane or a ramp with a turn on it, ask for the manufacturer's turning template for the specific model and hold the order until it is in hand.

Eleven records are not in the table, each for a stated reason, and six of them are mixers. Four of the six carry dimensions marked estimated or analogised: two are lower bounds — at least this big — rather than measurements, and two are another machine's dimensions borrowed whole. Those are working assumptions for internal transport planning, not specifications, and they are not published in any form, rounded or hedged. The other two depend on drawings whose binding to a model is an inference rather than a printed model number; they are marked provisional and stay out for the same reason. The rule the whole site runs on is that a figure is published when a document supports it. A dimension we have not got costs a buyer one email. A dimension we invented costs him a flat-rack invoice after the price has been agreed.

The remaining five records are crawler dozers, and their absence is a category difference rather than a data gap. They do have measured dimensions, but under a different caliper: length over the blade and ripper, width over the tracks, and a height taken to the cab roof on three of them, to the top of the exhaust stack on a fourth, and not stated for the fifth. They have no discharge volume and no drum, because they do not mix anything. Putting them in the same table as a mixer's length, width and height would invite a comparison that is not there to make. They are dealt with on the container page, where the only question asked of them is whether they clear a door, and the answer for all five is that they do not — every one is over the usable width, which is the failure that has no remedy.