Chassis
Brakes
The recommendation holds: four-wheel disc with Hydroboost, because a lopey-cam 454 won't hold the 16-18 inHg a vacuum booster needs. With 15-16 inch wheels, the Right Stuff THB7355DP-P kit at $2,635 is the one-box choice. It has 11 inch rotors front and rear, and that price is confirmed. A stock-height alternative…
Research note: all prices below were checked 2026-10-12 and come from vendor-page text or search-result snippets. summitracing.com, jegs.com and cjponyparts.com blocked direct page fetches (HTTP 403), so CJ Pony Parts, Summit and similar prices are search-snippet prices and can drift by a few dollars. Anything I could not confirm is marked "price not confirmed". Source numbers in [brackets] point to the Sources list at the end.
The pick
- Good
- ~$1,300-$1,800 (OE-style front rebuild, rebuilt rear drums, 11 inch vacuum booster kit BBCK91 at $331.99, plus an electric vacuum pump at $230-$420, lines, fluid; caliper and drum part prices not confirmed)
- Better
- ~$2,800-$3,400 (Wilwood 2-piston front plus rear disc plus Hydroboost plus proportioning valve plus lines). Using the Right Stuff THB7355DP-P kit at $2,635 plus about $225 stainless lines (TBS7380S) plus PS hoses and valve comes to about $3,000-$3,100.
- Best
- ~$5,300-$6,500 (ProSpindle $889 plus 13 inch 6R kit $2,156 plus rear disc about $800 plus Hydroboost $860-$970 plus master cylinder plus lines plus valve plus fluid; the Ridetech all-in kit is $5,795 without the booster)
My pick for this truck is a four-wheel disc system with Hydroboost, sized to the wheel diameter chosen in the wheels section.
Boost: Hydroboost. A 500 hp, lopey-cam 454 will not reliably make the vacuum a power booster needs [27][28]. A vacuum pump can fix this but adds a wired, failure-prone part to a car a teenager will drive, whereas Hydroboost reuses the power steering pump the truck already needs. It also gives about 2,000+ psi of line pressure [28] and has a stored accumulator for two to three assisted stops after a stall [29]. Pick the Hydratech HT-7T-3039K ($860, master cylinder extra) or a Performance Online Hydropower kit ($731.66-$967.80, master cylinder and valve included) for a bolt-in with a firewall plate and adjustable rod. Both avoid the "salvage-yard pedal" problem that forum owners ran into (the pedal pivot hole location is about 1" different between vacuum and hydroboost pedals) [37].
Front brakes, if wheels are 15"-16": Right Stuff THB7355DP-P ($2,635) is the most complete one-box solution. It covers front and rear discs, drop spindles, hydroboost, parking brake cables and braided hoses [5]. If the owner would rather keep stock-height and pick the pieces, CPP 7387SWBK-5OE-WWB-SP (
$999) plus SSBC A126-1BK-DS ($750-$840) is similar in capability.Front brakes, if wheels are 17" or larger (my preferred styling and sizing for a semi-classic truck with modern touches): Wilwood ProSpindle 831-14202 with the Superlite 6R 13.06" kit 140-15303-D, plus Wilwood braided flex lines. About $3,050 plus lines. It is more rotor than a 4,300 lb street truck strictly needs, but it removes any heat-fade concern with big meats on the back and a 500 hp engine, and it meets the 17" minimum [9][15]. If the owner prefers less cost, the 12.19" kit 140-15302-D on the same spindle is the "right-sized" option (about $1,200-$1,375 for the kit; some retailers title it Narrow Superlite 6R and others 4R, so confirm the caliper piston count before ordering).
Rear brakes: SSBC A126-1BK-DS (~$750-$840) or LEED RC6002 ($816-$850) if the owner wants rear discs. Both are designed to reuse the factory parking brake cables [22][24]. Test the parking brake on a real hill before sign-off. If the owner is wary of the parking brake problem [18], rebuilding the drums is a legitimate choice for a truck with strong front brakes and an adjustable proportioning valve.
Master cylinder and bias: use the MC supplied with the Hydroboost or 4-wheel kit (Hydroboost needs a master cylinder bore larger than 1" in at least one documented install, a Wilwood 1-1/8" [38]; the Right Stuff 4-wheel kit uses a 1" bore [5], so go by the kit maker's matched MC, not a loose part). Add a Wilwood adjustable proportioning valve (260-8420, ~$106) and set it with the procedure Wilwood publishes [39].
Lines: preformed stainless (Classic Tube, Right Stuff, or CJ) rather than rolling your own, because the 49-year-old frame lines are the part most likely to fail without warning, and a correct routing is part of the safety case for a teen driver.
If the owner picks the cheapest path (Good tier), do not go with a big cam plus a vacuum booster alone. Budget the electric vacuum pump too.
Why it matters
This truck will weigh roughly 4,300 lb and make about 500 hp with a lopey cam, and a teenager (Walter, ~2042) will drive it on a 35-minute interstate commute. Brake choice is a safety decision first and a styling decision second. The stock layout was designed for a 454 making about 215 net hp (that figure is my recollection, not sourced). The Big 10 package already specified "heavy-duty vacuum-assisted brakes" and a GVWR up to 6,200 lb [20], so the factory pieces were never marginal. The weak links on a 49-year-old truck are old lines and hoses, seized calipers, and a vacuum booster that depends on a cam the owner is about to make worse.
The most important decision in this section is how the brake pedal gets its power assist. A power booster needs roughly 16-18 inHg of vacuum to work properly [27]. A big-cam engine at idle in gear can make only 9-10 inHg, so you would need to add a vacuum pump to get back to ~18 [27]. With a lopey cam the vacuum also dips on every throttle blip and during a stall. Hydroboost runs off the power steering pump instead. It is independent of cam, gives roughly 2,000-2,500 psi of line pressure versus 800-1,400 psi for vacuum assist [28], and has an accumulator that gives two to three assisted stops if the engine dies [29]. For a truck with a rough-idle cam and a new driver in the seat, I recommend Hydroboost. It also frees up space on a big-block firewall. Kit makers say a Hydroboost unit needs about the same clearance as a 7" vacuum booster [10].
The second decision is front rotor size, which is tied to wheel diameter and spindle choice. The big Wilwood 13-14" six-piston kits need 17" or larger wheels [4][9][15]. The 12" two-piston and 12.19" kits clear 15" wheels [3][11][16]. This section's pick depends on the wheel and stance sections. The truck is lowered or leveled, so a 2" or 2.5" drop spindle is in play. A drop spindle also changes the brake and steering geometry.
Finally, the owner described the truck as "drums all around". My research and general GM knowledge say that is probably not right for a '77. Front discs have been available on C10s since 1971 [1], and every aftermarket catalog sells 1973-87 C10 conversion kits as "disc/drum" (front disc, rear drum) [2][12]. Treat the truck's real brake layout as a "verify on the truck" item. I could not find a source that confirms the exact RPO code for factory power brakes (J50 is my recollection and is unconfirmed).
Fitment & gotchas
- Lug count and axle flange: all the 1973-87 C10 kits I found are 5x5 unless otherwise stated [2][5]. CJ and Brothers also sell 6-lug versions for the 12-bolt (DBR321, DBR322-V, RDBK72-6) [12][25]. Count the lugs on the truck before ordering anything. The "Big 10" package is a heavy-duty half-ton; its brake parts are heavier than base, so confirm the front rotor and caliper part numbers on the truck.
- 12-bolt rear: the owner thinks it is a truck 12-bolt (8.875"). CJ lists its rear kits as fitting both 10- and 12-bolt axles in 1973-87 C10s [2]. SSBC, LEED and Brothers all list 12-bolt support [22][24][25]. Confirm the axle ID before buying, especially if the axle section moves to a Ford 9", a 14-bolt, or a different housing (see Interactions).
- ProSpindle ball joints: the Wilwood 831-14202 spindle needs 1973-87 upper and lower ball joints (not included), and 1971-72 trucks also need later outer tie rods [4]. The '77 already has the right joints, but budget for new ones since the front end is being rebuilt anyway.
- Flex lines: Wilwood front kits do not include flex hoses; the flyer says braided flex lines are required and must be ordered separately [4]. Wilwood lists 14", 16" and 18" kits in both 3/8-24 IF and metric 10x1.0 [4].
- Wheel clearance: Wilwood's 13" and 14" kits need 17"+ wheels [4][9][15]. Ridetech sells templates to verify fit before purchase and says the complete system "fits most 17" and larger wheels" [21]. Rear 12.88" rotors are similar. Wilwood says to use its wheel-clearance diagram before teardown; I did not retrieve backspacing numbers.
- Master cylinder bore: hydroboost needs a master cylinder bore larger than 1" in one documented install [38], while a different kit uses a 1" bore [5]. Do not mix unmatched parts. A '77 C30 owner with new discs reported a hard pedal from a large-bore stock master cylinder [37].
- Pedal: factory vacuum and Hydroboost pedal mounting holes differ by about 1" [37]. The Hydratech 3039K includes an adjustable pedal rod to avoid a pedal swap [11], and one forum build kept the stock pedal by matching the pivot-to-rod distance and cutting and threading the master cylinder pushrod [40]. Those are two different approaches; decide which before ordering.
- Power steering feel: owners report more steering assist after the swap [37][40]. The interaction with the steering section (see below) matters.
- Hydroboost bleeding: bleed the booster and the power steering system as a unit; Speedway has a how-to [41]. I did not retrieve the content.
- Rear parking brake: see caution above [18]. The factory cable reuse adapters are a selling point for SSBC and LEED. Plan for a longer break-in period and re-adjust after the first few hundred miles.
- Old hard lines: the line set must match bed length, model year (1973-80 versus 1981-87 differ) and the front/rear brake configuration. CJ sells separate kits for each [36].
- Proportioning valve: a disc/drum truck most needs a proportioning valve [39]. With the factory combination valve gone, the aftermarket valve is the only bias adjustment. The truck at 4,300 lb with a 454 up front will be nose heavy, so bias will likely need more front, not less.
How it touches other systems
- Steering: Hydroboost shares the power steering pump and puts the booster in series with the steering gear (pump to booster to gear to pump) [10][42]. A weak or leaking pump, a restricted cooler, or a clogged filter hurts braking, not just steering. A replacement pump needs enough flow and pressure (kit makers quote 800-1,400 psi pumps) [10]. If the steering section picks a rack and pinion or a different box, confirm the new setup supports Hydroboost (Hydratech says its 3040K works with rack-and-pinion conversions [32]; I did not verify the 3039K for rack-and-pinion). The old pump leaked; plan a new pump anyway.
- Engine and cam: the cam is the reason for the Hydroboost recommendation [27][28]. If the cam section instead picks a mild cam that makes 15+ inHg at idle in gear, a vacuum booster would work, but I would still go Hydroboost for the stall-protection reserve.
- Header and exhaust: Hydroboost hoses run near the headers and the exhaust. Use braided hose with sleeves, and avoid routing near a dump. Hydroboost units are compact and free up room on the driver side for full-length headers; the Hydratech product page says it requires no firewall modification [11].
- Wheels and tires: a 13"+ rotor forces 17" or larger wheels [4][9][15]. The wheel size and offset section must agree. Kits for 15" wheels top out at 12" or 12.19" rotors.
- Suspension and stance: ProSpindle and similar drop spindles lower the front by 2" or 2.5" and keep OE track width [4]. Combine them with springs, shocks and sway bar choices from the suspension section; do not drop with both springs and spindles unless the stance section says so.
- Rear axle: the rear brake kit and parking brake set-up depends on the axle section. Rear kits here are for the stock 12-bolt flange. If the axle section picks a Ford 9" (Ridetech lists 2.5" offset flange for the 9") [21], a 14-bolt, or a different housing, the rear brake kit changes. Rear disc kits from CPP and others have 9" Ford versions [43].
- Transmission and drivetrain: no direct link to the gearbox choice. A change to a manual (T56) would swap in a clutch pedal and a new pedal bracket, and the Hydroboost fitment (pedal pivot/rod position) would need rechecking. A 4L80E needs no change.
- Electrical and wiring: an electric vacuum pump (Good tier only) needs a fused, switched 12V feed, a vacuum switch and a check valve. Hydroboost needs none. The owner is comfortable doing wiring, but fewer failure points is still safer.
- Interior and pedal: new pedal pads, brake light switch position and the pedal-to-floor height all change with a Hydroboost pedal. Check pedal ratio and clearance to the new column and carpet.
- Brake lights, ABS and traction: none of the kits I researched include ABS. For a teen driver I would raise the possibility of a later add-on; I did not research bolt-in ABS for this platform.
Check on the truck
- What is on the truck now? Pull a front wheel and confirm: front disc or drum? Rear drum size? Does it have a power booster, and what size? The owner said "drums all around", but 1973-87 C10 catalogs treat front discs as stock [2][12].
- Count the lug nuts (5 or 6) and measure the bolt pattern. All kits above assume 5x5 unless noted.
- Confirm the rear axle ID: 12-bolt cover, axle tag, and flange measurement. An 8.875" truck 12-bolt is the owner's guess.
- Which wheel diameter will the wheels section choose (15", 16", 17", 18")? That decides whether the 13" Wilwood 6-piston kit is an option.
- Drop spindle or springs only? If drop spindles, it should be the same brand as the brake kit (Wilwood ProSpindle with Wilwood brakes; Right Stuff drop spindles with Right Stuff kits). Detroit Speed owners must buy kits for Detroit Speed spindles [17].
- Is the power steering box original, or is a steering swap planned? Hydroboost works with the original Saginaw system, and the steering swap could change the plumbing.
- How much hill parking does the truck do? That decides if rear disc parking brakes are worth the cable headaches [18].
- Is the owner willing to bleed a Hydroboost system and flush brake fluid every one to two years?
- What is the cam's idle vacuum? Measure manifold vacuum in gear on the current engine and again after the cam swap. If the idle is 16+ inHg, the vacuum-booster path is still possible.
- Do you want ABS? Not researched; ask a brake vendor (Wilwood, Right Stuff) before committing.
Fact-check notes
Adversarial check run 2026-10-12. Vendor pages fetched directly (returned content): AZ Pro Performance (Hydratech 3039K, 3040K, Wilwood 140-15303-D), FP Auto Parts (THB7355DP-P, TDC7325DP-P, TDC7355DP-P), Performance Online (HB2-T7387, HB-T7387PBO), AAM/LEED RC6002, Ridetech complete kit, rpui.com TBS7380S, subimods Motul, Wilwood fluid page, All Chevy Performance, gmsquarebody hydroboost thread. Blocked (HTTP 403 or bot wall): Summit, JEGS, CJ Pony Parts, underhoodservice, Walmart; Wilwood fl427 PDF returned unreadable binary. classicperform.com page returned 404.
Confirmed unchanged: Hydratech HT-7T-3039K $860 (fits 1973-79, so right for a '77); Right Stuff THB7355DP-P $2,635 (11" rotors front and rear, 15"+ wheels, 5x5); POL HB2-T7387 $731.66 and HB-T7387PBO $967.80; Wilwood 140-15303-D $2,155.71, minimum wheel 17"; Ridetech kit $5,795; Right Stuff TDC7325DP-P $1,482.00; Wilwood ProSpindle $889.34; BBCK91 $331.99; Street Beast $872.99 CJ / $898.99 Summit; Brothers RDBK72-5 $972.95; hydroboost vacuum rationale (All Chevy Performance: big cams cut vacuum, MC bore over 1 inch).
Corrected:
- Right Stuff part numbers: TDC7325DBP is actually TDC7325DP-P; TDC7355DBP is TDC7355DP-P.
- CPP 7387SWBK-5OE-WWB-SP: $999, not $1,008; dead classicperform.com link replaced with the CJ page.
- LEED RC6002: MSRP is $849.99 (draft said $749.95); calipers are zinc plated.
- Wilwood fluid: EXP 600 Plus is $29.66, 626 F dry / 417 F wet (draft said $24.22, 594/399). Motul RBF 600 is $23.58, 593/420 F, and is not the "same" as Wilwood's figures.
- Proportioning valve: the enginemaster.com.au link priced in AUD ($201.85 AUD); replaced with a US retailer, about $105.81.
- Baer: the draft's 4301391B was the 6-lug kit; the 5-lug black kit is 4301390B, about $3,779 (snippet).
- Classic Tube CT1155 is the standard (non-power) brake kit, so it was wrong for this power-brake truck; replaced the example with the verified Right Stuff TBS7380S ($225.75) and flagged that the right Classic Tube kit number is unconfirmed.
- Added 12.19 inch Wilwood kit price (~$1,199-$1,373) so the right-sized option has a number; SSBC A126-1BK-DS now shown as $748-$838 because the $796 Summit price could not be re-fetched.
- Hydratech 3039K does not include the master cylinder; added to the notes and cost.
- Best-tier total lowered to ~$5,300-$6,500 based on verified component prices.
Recommendation check: Hydroboost with four-wheel disc stays the right call for a lopey-cam 454 on pump gas, a teen driver and a 65-70 mph commute. Still unverified: the 1977 truck's factory brake layout (owner says drums; catalogs say front discs standard), PS pump location on a big-block (Hydratech wants it on the driver side), 5-lug 5x5 (all 1971-87 2WD C10s are 5-lug, so 6-lug kits do not apply), the Wilwood fl427 minimum wheel for the 12.19 inch kit, and rear-disc parking brake performance. ABS remains unresearched.
Sources 46
- CJ Pony Parts, C10 front disc brake kit listing (states discs were not offered on C10 until 1971): cjponyparts.com
- CJ Pony Parts, rear disc kits for 1973-87 C10 (10/12-bolt): cjponyparts.com
- Wilwood press release PR-287 (11.86" Classic Series Superlite 6R, "clearance inside most styles of 15" wheels"): wilwood.com
- Wilwood flyer fl427, 2.50" drop C10 ProSpindle and brake kits, part numbers: wilwood.com
- FP Auto Parts, Right Stuff 4-wheel Hydraulic Assist kit THB7355DP-P: fpautoparts.com
- FP Auto Parts, Right Stuff power front disc kit TDC7325DP-P: fpautoparts.com
- FP Auto Parts, Right Stuff TDC7355DP-P 4-wheel power disc kit: fpautoparts.com
- Wilwood ProSpindle 831-14202 installation instructions (read from PDF): wilwood.com
- Wilwood ProSpindle 831-14201 instructions: wilwood.com
- Performance Online, Hydropower hydroboost kit HB2-T7387: performanceonline.com
- AZ Pro Performance, Master Power/Hydratech HT-7T-3039K: azproperformance.com
- CJ Pony Parts, 6-lug rear disc kit DBR321 (search listing): cjponyparts.com
- CJ Pony Parts, Raybestos rotor/hub assembly BR96 (factory rotor spec 11.86 in search result): cjponyparts.com
- CJ Pony Parts, front disc brake kit DBF399: cjponyparts.com
- AZ Pro Performance, Wilwood 140-15303-D: azproperformance.com
- Suspension Superstore, Wilwood 12.19" Dynalite front/rear kit 7387C10WW: suspensionsuperstore.com
- Detroit Speed brake hose bracket 050402DS and Wilwood 140-16781-DR: detroitspeed.com and detroitspeed.com
- gmsquarebody.com, rear disc conversion thread (parking brake complaints): gmsquarebody.com and forabodiesonly.com
- gmsquarebody.com, rear disc thread (drums vs discs): gmsquarebody.com
- Classic Industries, Square Body special editions (BIG-10 package): news.classicindustries.com
- Ridetech, Wilwood complete 6-piston Superlite system for C10: ridetech.com
- Speedway Motors, SSBC A126-1BK-DS: speedwaymotors.com
- Summit Racing, SSBC A126-1BK-DS: summitracing.com
- LEED Brakes RC6002: suppliers.theaamgroup.com
- CJ Pony Parts, Brothers Trucks RDBK72-5: cjponyparts.com
- wheelfront.com / rpui.com / Jegs, Right Stuff listings (TDC7325DB, THB7325D, T73DC05): wheelfront.com and jegs.com
- Vacuum requirement (16-18 inHg; 9-10 inHg big-cam idle) came from search-result summaries of Street Muscle "Gimme a Boost" and a FordMuscle electric-pump article (pages returned HTTP 410 on fetch, so unverified in full): streetmusclemag.com and fordmuscle.com . Also All Chevy Performance, Chevelle Hydro-Boost install (big cam vacuum, 1-1/8" MC, hose kit ~$350): digital.allchevyperformance.com
- Search result summary of Hydroboost versus vacuum pressure: sportsmobileforum.com
- Operation, Diagnosis and Repair of Hydro-Boost Power Assist Systems (accumulator, 2-3 assisted stops): underhoodservice.com
- JEGS LEED electric vacuum pump kits and OER universal pump: jegs.com and restorationperformance.com
- CJ Pony Parts and Summit, CPP Street Beast hydraulic assist kit: cjponyparts.com
- AZ Pro Performance, Hydratech HT-7T-3040K (1980-87): azproperformance.com
- Wilwood 260-8420 listing and Speedway residual vs proportioning valve article: enginemaster.com.au and speedwaymotors.com
- Wilwood brake fluid page and Motul RBF 600 listing: wilwood.com and subimods.com
- gmsquarebody.com, 2000s hydroboost into a square (NiCopp, Hawk HP+, Wilwood proportioning valve, pedal hole): gmsquarebody.com
- CJ Pony Parts, stainless brake line kits for 1973-87 C10: cjponyparts.com
- gmsquarebody.com, hydro boost thread, pedal hole, steering assist, big-bore MC: gmsquarebody.com
- All Chevy Performance, same article as 27 (1-1/8" Wilwood MC).
- Wilwood, how a proportioning valve works: shop.wilwood.com
- gmsquarebody.com post (hydroboost with stock pedal, modified pushrod): gmsquarebody.com
- Speedway Motors, Hydroboost 101 how to bleed (listed in search results, not fetched): speedwaymotors.com
- gmsquarebody.com, Hydro boost vs vacuum boost: gmsquarebody.com
- CJ Pony Parts, CPP 12" rear disc kit for Ford 8"/9" in C10: cjponyparts.com
- gmsquarebody.com, hydroboost or not: gmsquarebody.com
- gmsquarebody.com, hydroboost post (parts from a 1985 3/4-ton, pedal): gmsquarebody.com
- Wilwood press release PR-223 and Wilwood C10 ProSpindle search listing: wilwood.com