{"id":2919,"date":"2026-07-24T14:50:19","date_gmt":"2026-07-24T14:50:19","guid":{"rendered":"https:\/\/bravofabs.com\/cnc-machined-aluminum-gearbox-transmission-case\/"},"modified":"2026-09-10T13:08:57","modified_gmt":"2026-09-10T05:08:57","slug":"cnc-machined-aluminum-gearbox-transmission-case","status":"publish","type":"post","link":"https:\/\/bravofabs.com\/cnc-machined-aluminum-gearbox-transmission-case\/","title":{"rendered":"CNC Machined Aluminum Gearbox &amp; Transmission Cases | Custom Manufacturing"},"content":{"rendered":"\n<h1 class=\"wp-block-heading\">CNC Machined Aluminum Gearbox &amp; Transmission Cases<\/h1>\n\n\n\n<p class=\"wp-block-paragraph\">Precision CNC machining of <strong>aluminum gearbox housings<\/strong>, transmission cases, and drivetrain components \u2014 from prototype to production. Tolerances down to \u00b10.005 mm, 3\/4\/5-axis capability, ISO-certified quality. Serving automotive, industrial machinery, robotics, and aerospace clients worldwide.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Key Takeaways<\/h2>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Materials:<\/strong> 6061-T6 (general purpose) and 7075-T6 (high-strength) aluminum alloys \u2014 full spec table below<\/li>\n<li><strong>Capabilities:<\/strong> 3-axis to 5-axis CNC machining for housings, covers, bearing seats, and oil passages<\/li>\n<li><strong>Tolerances:<\/strong> Standard \u00b10.01 mm, precision \u00b10.005 mm for bore diameters and gasket surfaces<\/li>\n<li><strong>Industries:<\/strong> Automotive EV\/racing, industrial pumps, robotics actuators, aerospace structures<\/li>\n<li><strong>Quality:<\/strong> CMM inspection, material certification, surface roughness testing on every batch<\/li>\n<li><strong>Turnaround:<\/strong> 7-day prototype lead time, no minimum order quantity<\/li>\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading\">Why Aluminum for Gearbox &amp; Transmission Housings<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Aluminum is the dominant material for gearbox and transmission cases in modern manufacturing. Compared to cast iron or steel, aluminum offers three decisive advantages for drivetrain components:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Weight reduction:<\/strong> Aluminum is 65% lighter than steel \u2014 critical for <a href=\"https:\/\/bravofabs.com\/cnc-machining-service\/\">automotive CNC machining<\/a> applications where every kilogram affects fuel economy and acceleration. A typical aluminum gearbox housing weighs 4-8 kg versus 12-22 kg in cast iron.<\/li>\n<li><strong>Thermal management:<\/strong> With thermal conductivity of 150-170 W\/m\u00b7K (3\u00d7 that of steel), aluminum gearbox cases act as heat sinks, dissipating friction heat from gears and bearings more efficiently. This reduces oil temperature by 10-15\u00b0C in sustained operation.<\/li>\n<li><strong>Corrosion resistance:<\/strong> The natural aluminum oxide layer provides inherent protection against moisture and road salt \u2014 no plating required for most environments. For marine or chemical exposure, hard anodizing adds a 25-50 \u03bcm protective layer.<\/li>\n<li><strong>Machinability:<\/strong> Aluminum&#8217;s lower cutting forces (compared to steel or titanium) enable faster cycle times, reducing per-part cost by 30-50% for production volumes. Tool life is 3-5\u00d7 longer than when machining steel alloys.<\/li>\n<\/ul>\n\n\n\n<p class=\"has-background wp-block-paragraph\" style=\"background-color:#f8f9fb;padding:14px\"><strong>Best for:<\/strong> Automotive EV housings, racing transmission cases, industrial pump bodies, and any application where weight \u00d7 strength matters.<br><strong>Avoid when:<\/strong> Extreme wear environments (rock crushers, mining equipment) \u2014 consider hardened steel or ductile iron instead.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Aluminum Alloy Selection for Gearbox Applications<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Choosing the right aluminum grade depends on your strength, weight, and corrosion requirements. Below is a comparison of the most common alloys used in gearbox and transmission manufacturing:<\/p>\n\n\n\n<figure class=\"wp-block-table\"><table style=\"width:100%;border-collapse:collapse;margin:15px 0\">\n<thead><tr style=\"background:#004c97;color:#fff\"><th>Alloy<\/th><th>Tensile Strength<\/th><th>Yield Strength<\/th><th>Hardness<\/th><th>Corrosion<\/th><th>Best Application<\/th><\/tr><\/thead>\n<tbody>\n<tr style=\"border-bottom:1px solid #e5e5e5\"><td><strong>6061-T6<\/strong><\/td><td>310 MPa<\/td><td>276 MPa<\/td><td>95 HB<\/td><td>Good<\/td><td>General-purpose housings, covers, mounting flanges<\/td><\/tr>\n<tr style=\"border-bottom:1px solid #e5e5e5\"><td><strong>7075-T6<\/strong><\/td><td>572 MPa<\/td><td>503 MPa<\/td><td>150 HB<\/td><td>Moderate<\/td><td>High-stress transmission cases, racing gearboxes<\/td><\/tr>\n<tr style=\"border-bottom:1px solid #e5e5e5\"><td><strong>2024-T3<\/strong><\/td><td>470 MPa<\/td><td>325 MPa<\/td><td>120 HB<\/td><td>Poor<\/td><td>Aerospace gearbox structures (with coating)<\/td><\/tr>\n<tr style=\"border-bottom:1px solid #e5e5e5\"><td><strong>7050-T7451<\/strong><\/td><td>524 MPa<\/td><td>469 MPa<\/td><td>150 HB<\/td><td>Moderate<\/td><td>Aerospace transmission housings, stress-corrosion resistant<\/td><\/tr>\n<tr><td><strong>A356-T6 (Cast)<\/strong><\/td><td>230 MPa<\/td><td>165 MPa<\/td><td>75 HB<\/td><td>Excellent<\/td><td>Complex geometry, lower cost for volumes >500 pcs<\/td><\/tr>\n<\/tbody>\n<\/table><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">For most industrial gearbox applications, <strong>6061-T6<\/strong> offers the best balance of strength, machinability, and cost. For performance applications where weight savings justify the premium, <strong>7075-T6<\/strong> delivers near-steel strength at one-third the weight. See our <a href=\"https:\/\/bravofabs.com\/cnc-machining-aluminum\/\">complete aluminum CNC machining guide<\/a> for detailed speed\/feed recommendations.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">CNC Machining Capabilities for Drivetrain Components<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Gearbox housings demand multi-face machining with <strong>tight positional tolerances between bore centers<\/strong>. Our CNC capabilities cover the full range of complexity:<\/p>\n\n\n\n<figure class=\"wp-block-table\"><table style=\"width:100%;border-collapse:collapse;margin:15px 0\">\n<thead><tr style=\"background:#004c97;color:#fff\"><th>Machine Type<\/th><th>Max Part Size<\/th><th>Best For<\/th><th>Typical Tolerance<\/th><\/tr><\/thead>\n<tbody>\n<tr style=\"border-bottom:1px solid #e5e5e5\"><td><strong>3-Axis CNC<\/strong><\/td><td>800\u00d7500\u00d7500 mm<\/td><td>Flat covers, mounting plates, simple 2-face housings<\/td><td>\u00b10.01 mm<\/td><\/tr>\n<tr style=\"border-bottom:1px solid #e5e5e5\"><td><strong>4-Axis CNC<\/strong><\/td><td>600\u00d7400\u00d7400 mm<\/td><td>Multi-face machining in one setup \u2014 shaft bores, oil passages, flange faces<\/td><td>\u00b10.008 mm<\/td><\/tr>\n<tr style=\"border-bottom:1px solid #e5e5e5\"><td><strong>5-Axis CNC<\/strong><\/td><td>400\u00d7400\u00d7350 mm<\/td><td>Complex curved surfaces, impeller housings, aerospace-grade parts<\/td><td>\u00b10.005 mm<\/td><\/tr>\n<tr><td><strong>CNC Turning<\/strong><\/td><td>\u00d8400\u00d7600 mm<\/td><td>Shaft sleeves, bearing housings, circular flanges<\/td><td>\u00b10.005 mm<\/td><\/tr>\n<\/tbody>\n<\/table><\/figure>\n\n\n\n<p class=\"has-background wp-block-paragraph\" style=\"background-color:#f8f9fb;padding:14px\"><strong>Best for:<\/strong> Bore diameters from \u00d820 to \u00d8300 mm, bore-to-bore center distance tolerances of \u00b10.01 mm, flatness of 0.02 mm\/m on sealing surfaces.<br><strong>Avoid when:<\/strong> Single-setup 3-axis parts under 100\u00d7100 mm \u2014 our <a href=\"https:\/\/bravofabs.com\/cnc-turning-service\/\">CNC turning service<\/a> may be more cost-effective for small rotational parts.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Typical Gearbox Parts We Manufacture<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Over the past decade, BravoFabs has machined thousands of drivetrain components for clients in 11 countries. The most common parts include:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Gearbox main housings<\/strong> \u2014 Single-piece aluminum bodies with integrated bearing seats, oil galleries, and mounting points. Typical tolerances: bore \u00d8 \u00b10.01 mm, flatness 0.02 mm\/100 mm.<\/li>\n<li><strong>Transmission cases (manual &amp; automatic)<\/strong> \u2014 Split-case or monoblock designs with internal ribbing for structural rigidity. Common in EV reduction gearboxes and industrial power transmission.<\/li>\n<li><strong>Bearing housings &amp; retainer plates<\/strong> \u2014 Precision-bored seats for ball and roller bearings, often with threaded mounting holes and dowel pin locations for alignment.<\/li>\n<li><strong>Sliding sleeves &amp; shift forks<\/strong> \u2014 Wear-resistant components machined from 7075-T6 with hard-anodized contact surfaces. Typical hardness: 400-500 HV after anodizing.<\/li>\n<li><strong>Oil pump bodies &amp; valve blocks<\/strong> \u2014 Complex internal channels for hydraulic fluid routing, pressure-tested to 20+ bar after machining.<\/li>\n<li><strong>Differential cases &amp; axle housings<\/strong> \u2014 Large-diameter bores with cross-drilled lubrication holes. Often machined from 6061-T6 with post-machining T6 heat treatment.<\/li>\n<li><strong>Custom motor adapter plates<\/strong> \u2014 Precision-machined interface plates connecting motors to gearboxes, with dowel holes for alignment and threaded bolt patterns.<\/li>\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading\">Surface Finishes &amp; Treatments<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Post-machining surface treatments extend the life and performance of aluminum gearbox components:<\/p>\n\n\n\n<figure class=\"wp-block-table\"><table style=\"width:100%;border-collapse:collapse;margin:15px 0\">\n<thead><tr style=\"background:#004c97;color:#fff\"><th>Treatment<\/th><th>Thickness<\/th><th>Hardness<\/th><th>Best For<\/th><\/tr><\/thead>\n<tbody>\n<tr style=\"border-bottom:1px solid #e5e5e5\"><td><strong>As-Machined<\/strong><\/td><td>\u2014<\/td><td>95-150 HB<\/td><td>Prototypes, internal components not exposed to wear<\/td><\/tr>\n<tr style=\"border-bottom:1px solid #e5e5e5\"><td><strong>Clear Anodizing<\/strong><\/td><td>5-15 \u03bcm<\/td><td>200-300 HV<\/td><td>General corrosion protection, cosmetic finish<\/td><\/tr>\n<tr style=\"border-bottom:1px solid #e5e5e5\"><td><strong>Hard Anodizing<\/strong><\/td><td>25-50 \u03bcm<\/td><td>400-500 HV<\/td><td>Wear surfaces, sliding sleeves, outdoor exposure<\/td><\/tr>\n<tr style=\"border-bottom:1px solid #e5e5e5\"><td><strong>Chemical Film (Alodine)<\/strong><\/td><td>1-3 \u03bcm<\/td><td>\u2014<\/td><td>Electrical conductivity required, MIL-DTL-5541<\/td><\/tr>\n<tr><td><strong>Powder Coating<\/strong><\/td><td>60-120 \u03bcm<\/td><td>\u2014<\/td><td>Cosmetic outer covers, color-matched branding<\/td><\/tr>\n<\/tbody>\n<\/table><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">For transmission cases with internal oil passages, we recommend <strong>hard anodizing<\/strong> on all fluid-contact surfaces to prevent erosion from hot oil flow. External surfaces can be left as-machined or anodized for corrosion resistance.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Quality Inspection Process<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Every gearbox housing undergoes a <strong>four-stage inspection protocol<\/strong> before shipment:<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>CMM Dimensional Inspection<\/strong> \u2014 Bore diameters, center distances, flatness, and perpendicularity verified to \u00b10.003 mm using a coordinate measuring machine. Full dimensional reports provided with every batch.<\/li>\n<li><strong>Surface Roughness Testing<\/strong> \u2014 Gasket sealing surfaces checked with a profilometer. Target: Ra 0.8-1.6 \u03bcm for sealing surfaces, Ra 1.6-3.2 \u03bcm for non-critical areas.<\/li>\n<li><strong>Thread Inspection<\/strong> \u2014 Every tapped hole checked with go\/no-go thread gauges. Thread classes: 2B\/3B (inch) or 6H (metric) as standard.<\/li>\n<li><strong>Material Certification<\/strong> \u2014 Mill test reports (EN 10204 3.1 or equivalent) included with every shipment, verifying chemical composition and mechanical properties of the raw aluminum billet.<\/li>\n<\/ol>\n\n\n\n<p class=\"wp-block-paragraph\">For complete quality documentation on our inspection capabilities, see our <a href=\"https:\/\/bravofabs.com\/qc-devices-in-metal-fabrication\/\">QC inspection devices guide<\/a> and <a href=\"https:\/\/bravofabs.com\/quality-control-in-metal-fabrication\/\">quality control process overview<\/a>.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Industries &amp; Applications<\/h2>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Automotive:<\/strong> EV motor housings requiring tight stator bore tolerances; racing transmission cases machined from 7075-T6 billet; differential housings for performance vehicles.<\/li>\n<li><strong>Industrial Machinery:<\/strong> Pump housings for hydraulic systems up to 350 bar; compressor bodies with integrated cooling fins; hydraulic valve manifolds with cross-drilled galleries.<\/li>\n<li><strong>Robotics:<\/strong> Precision joint housings with bearing seats for harmonic drive reducers; lightweight actuator bodies for collaborative robots; motor-gearbox interface plates.<\/li>\n<li><strong>Aerospace:<\/strong> Lightweight aluminum gearbox structures for UAV propulsion systems; aircraft actuator housings meeting AS9100 traceability requirements.<\/li>\n<li><strong>Marine:<\/strong> Corrosion-resistant outdrive housings with hard-anodized protection against saltwater; propeller shaft bearing carriers in 6061-T6.<\/li>\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading\">Why Choose BravoFabs for Gearbox Machining<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">We are not a general machine shop \u2014 <strong>drivetrain components are a core competency<\/strong>. Our in-house facility in Dongguan, China has dedicated fixturing for gearbox-class workpieces and processes refined over 10+ years of CNC machining experience.<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>In-house facility with full material traceability<\/li>\n<li>7-day turnaround on prototypes \u2014 from STEP file to first article inspection<\/li>\n<li>No minimum order \u2014 1 piece prototype to 10,000+ production run<\/li>\n<li>Free DFM (Design for Manufacturing) review identifying cost-saving opportunities before cutting metal<\/li>\n<li>DHL\/FedEx\/UPS worldwide shipping with full export documentation<\/li>\n<\/ul>\n\n\n\n<div class=\"wp-block-group has-light-gray-background-color has-background is-layout-constrained wp-container-core-group-is-layout-e86b207e wp-block-group-is-layout-constrained\" style=\"border-color:#1e73be;border-width:2px;padding-top:20px;padding-right:24px;padding-bottom:20px;padding-left:24px\">\n\n\n<h3 class=\"wp-block-heading\">Need a Custom Gearbox Housing? Get a CNC Quote<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">BravoFabs provides precision CNC machining for aluminum gearbox housings, transmission cases, and drivetrain components. Our ISO-certified facility delivers tight-tolerance housings for automotive, industrial, and aerospace clients in the US, Germany, and across Europe.<\/p>\n\n\n\n<div class=\"wp-block-buttons is-layout-flex wp-block-buttons-is-layout-flex\">\n\n<div class=\"wp-block-button\"><a class=\"wp-block-button__link has-white-color has-vivid-cyan-blue-background-color has-text-color has-background wp-element-button\" href=\"https:\/\/bravofabs.com\/contact\/\" style=\"border-radius:6px\">Request a CNC Machining Quote \u2192<\/a><\/div>\n\n<\/div>\n\n\n<\/div>\n\n\n\n<div class=\"wp-block-group is-layout-constrained wp-container-core-group-is-layout-cbfb3306 wp-block-group-is-layout-constrained\" style=\"border-left-color:#2563eb;border-left-width:4px;border-left-style:solid;background-color:#f0f4ff;margin-top:32px;margin-bottom:0;padding-top:12px;padding-bottom:12px;padding-left:20px;padding-right:24px\">\n\n\n<h4 class=\"wp-block-heading\" style=\"font-size:15px;font-style:normal;font-weight:700;line-height:1.4;margin-top:0;margin-bottom:8px\">\ud83d\udd17 Related Manufacturing Services &amp; Articles<\/h4>\n\n\n\n<ul class=\"wp-block-list\" style=\"font-size:14px;line-height:1.7;padding-left:18px\">\n<li><strong><a href=\"https:\/\/bravofabs.com\/cnc-machining-service\/\">CNC Machining Service<\/a><\/strong> \u2014 precision 3\/4\/5-axis milling and turning for custom metal parts<\/li>\n<li><strong><a href=\"https:\/\/bravofabs.com\/cnc-turning-service\/\">CNC Turning Services<\/a><\/strong> \u2014 custom shafts, bushings, and rotational parts<\/li>\n<li><strong><a href=\"https:\/\/bravofabs.com\/cnc-machining-aluminum\/\">CNC Machining Aluminum Guide<\/a><\/strong> \u2014 grades, speeds, feeds, and surface finish recommendations<\/li>\n<li><strong><a href=\"https:\/\/bravofabs.com\/qc-devices-in-metal-fabrication\/\">QC Inspection Devices for CNC Machining<\/a><\/strong> \u2014 CMM, hardness testers, and surface roughness tools<\/li>\n<li><strong><a href=\"https:\/\/bravofabs.com\/tolerance-standards-in-metal-fabrication\/\">Tolerance Standards in Metal Fabrication<\/a><\/strong> \u2014 ISO 2768, GD&amp;T, and when to use each<\/li>\n<\/ul>\n\n\n<\/div>\n\n<div class=\"rs-section\"><div class=\"rs-container\"><h2>Explore Related Manufacturing Services<\/h2><div class=\"rs-grid\"><div class=\"rs-card\"><a href=\"\/cnc-machining-services\/\">CNC Machining Services<\/a><p>Precision CNC milling, turning &amp; 5-axis machining.<\/p><\/div><div class=\"rs-card\"><a href=\"\/sheet-metal-fabrication-services\/\">Sheet Metal Fabrication<\/a><p>Laser cutting, bending, welding &amp; assembly.<\/p><\/div><\/div><\/div><\/div>","protected":false},"excerpt":{"rendered":"<p>CNC Machined Aluminum Gearbox &amp; Transmission Cases Precision CNC machining of aluminum gearbox housings, transmission cases, and drivetrain components \u2014 from prototype to production. Tolerances down to \u00b10.005 mm, 3\/4\/5-axis capability, ISO-certified quality. Serving automotive, industrial machinery, robotics, and aerospace clients worldwide. Key Takeaways Materials: 6061-T6 (general purpose) and 7075-T6 (high-strength) aluminum alloys \u2014 full [&hellip;]<\/p>\n","protected":false},"author":0,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_seopress_titles_title":"CNC Machined Aluminum Gearbox & Transmission Cases \u2014 Custom CNC Manufacturing | BravoFabs","_seopress_titles_desc":"Custom CNC machining of aluminum gearbox housings and transmission cases. 3\/4\/5-axis precision, tolerances \u00b10.005 mm. 6061 and 7075 aluminum alloys. 7-day prototype turnaround, free quote.","_seopress_robots_index":"","_seopress_robots_follow":"","_seopress_robots_imageindex":"","_seopress_robots_snippet":"","_seopress_robots_primary_cat":"","_seopress_robots_breadcrumbs":"","_seopress_robots_freeze_modified_date":"","_seopress_robots_custom_modified_date":"","_seopress_robots_canonical":"","_seopress_social_fb_title":"","_seopress_social_fb_desc":"","_seopress_social_fb_img":"","_seopress_social_fb_img_attachment_id":0,"_seopress_social_fb_img_width":0,"_seopress_social_fb_img_height":0,"_seopress_social_twitter_title":"","_seopress_social_twitter_desc":"","_seopress_social_twitter_img":"","_seopress_social_twitter_img_attachment_id":0,"_seopress_social_twitter_img_width":0,"_seopress_social_twitter_img_height":0,"_seopress_redirections_value":"","_seopress_redirections_enabled":"","_seopress_redirections_enabled_regex":"","_seopress_redirections_logged_status":"","_seopress_redirections_param":"","_seopress_redirections_type":0,"_seopress_analysis_target_kw":"CNC machined aluminum gearbox transmission case","footnotes":""},"categories":[1],"tags":[],"class_list":["post-2919","post","type-post","status-publish","format-standard","category-uncategorized"],"_links":{"self":[{"href":"https:\/\/bravofabs.com\/wp-json\/wp\/v2\/posts\/2919","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/bravofabs.com\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/bravofabs.com\/wp-json\/wp\/v2\/types\/post"}],"replies":[{"embeddable":true,"href":"https:\/\/bravofabs.com\/wp-json\/wp\/v2\/comments?post=2919"}],"version-history":[{"count":3,"href":"https:\/\/bravofabs.com\/wp-json\/wp\/v2\/posts\/2919\/revisions"}],"predecessor-version":[{"id":3043,"href":"https:\/\/bravofabs.com\/wp-json\/wp\/v2\/posts\/2919\/revisions\/3043"}],"wp:attachment":[{"href":"https:\/\/bravofabs.com\/wp-json\/wp\/v2\/media?parent=2919"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/bravofabs.com\/wp-json\/wp\/v2\/categories?post=2919"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/bravofabs.com\/wp-json\/wp\/v2\/tags?post=2919"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}