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| T-4000 | One (1) RV Fresh Water 40 Gallon Tank, Grey Water

  • Based on 133 reviews
Condition: New
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Availability: In Stock.
Fulfilled by classAcustoms

Arrives Jun 25 – Jun 30
Order within 14 hours and 6 minutes
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Features

  • 40 Gallon Fresh or Gray Water Holding Tank Manufactured by Class A Customs - Made from NSF Approved Materials - Fresh & Drinking Water Safe - Can be used for Fresh or Gray Water Storage
  • WATER TANK MEASUREMENTS: 39 1/2 Longest Length (not including fittings) x 13 x 18 - Tank can sit on any side - rotate tank to change height or width Average Thickness 7/32 +/- Please view photos. (Due to the manufacturing process +/- .25" on each measurement)
  • TANK BUILT-IN FITTINGS: (TWO) 1.5" Female NPT Fitting - fitting is sealed and watertight, to use remove membrane with razor knife (TWO) .5" Female NPT Fitting - fitting is open DO NOT over-tighten fitting damage will occur, use plastic connecting fittings as metal will damage threads.
  • NON-PRESSURIZED TANK: tank must be vented allowing air in and out during use. DO NOT make a sealed connection with a garden hose directly to tank, this is a pressurized connection and will cause tank to explode causing damage. For filling tank it is recommended to use a fill dish or other gravity process.
  • Great extra water storage in RV, pop-up camper, off-road vehicles, concession trailers, hot dog carts, smaller food vendors and portable hand washing sinks. Class A Customs Manufactures this item in the USA in Elkhart, Indiana. Tanks are made in a warehouse clean each tank prior to use to remove any debris, scuffs or marking from the manufacturing process.

Description

FRESH/DRINKING WATER SAFE – MADE IN THE USA by Class A Customs using NSF Certified Materials Tank & fittings made from DOW NSF International NSF/ANSI Std 61 approved Medium Density Polyethylene (MDPE) Resin SEAMLESS One-piece construction, no seams to burst COLOR Creamy White you can see waterline through tank. OEM PART No retail box - no install instructions Have a certified technician install all parts to prevent product damage and personal injury PREPARATION Tanks are made in a warehouse clean each tank prior to use to remove any debris, scuffs or marking from the manufacturing process. TANK MUST BE VENTED allowing air in and out when in use. DO NOT PRESSURIZE TANK do not make a sealed connection from garden hose directly to tank damage will occur. DO NOT over-tighten fittings damage will occur. MOUNTING & BRACING Place tank on level surface and brace to prevent tank from moving during transit. DO NOT hang tank by straps. DO NOT place weight on tank. FOOD VENDORS - BEFORE PURCHASING - Verify all requirements with health department where inspection will be made.

Brand: classAcustoms


Color: White


Material: Polyethylene (PE), Resin


Product Dimensions: 39.5"L x 18"W x 13"H


Capacity: 40 Gallons


Brand Name: classAcustoms


UPC: 808890308967


Manufacturer: Class A Customs


Model Number: T-4000


Manufacturer Part Number: 40-gal


Unit Count: 1.0 Count


Manufacturer Warranty Description: Manufacturer warranty covers manufacturer defect on manufacturer installed fittings and tank. Using this tank for any purpose other than fresh or gray water storage will void any/all warranty. Do not use tanks for sewage or fuel.


Item Dimensions L x W x H: 39.5"L x 18"W x 13"H


Capacity: 40 Gallons


Item Weight: 49 Pounds


Color: White


Shape: Rectangular


Material Type: Polyethylene (PE), Resin


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Jun 25 – Jun 30

Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

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Top Amazon Reviews


  • Can't find a better deal Can't find a better deal
Amazing fresh water tanks for my school bus conversion. No leaks, no bulging. All the npt holes on a single side of the tank is perfect compared to some other over engineered RV tanks. Excellent price for these. I got two 40gal for a total of 80gal of fresh water.
Reviewed in the United States on November 9, 2025 Reviewed in the United States on November 9, 2025 by KrisK

  • Good
👍
Reviewed in the United States on March 7, 2026 by javier falcon

  • Have water
Does the job
Reviewed in the United States on November 21, 2025 by No not happy it will not screw in to the hose it came with

  • Camper water tank
Fit perfectly under our bed and was in great condition.
Reviewed in the United States on August 7, 2024 by Dave Alft

  • 40 Gal. Would buy again.
I got the 40 gal version. No leaks. It didn't have a unreasonable amount of distortion when full. I did have a little trouble getting brass 1/2" PEX fittings to thread in without cross threading. I was using Teflon tape and that seemed to be causing the issue. Eventually I figured out that leaving the first thread of the brass exposed, so the brass engaged the threads with no Teflon and then the Teflon started, they would thread in with no issue. ... show more
Reviewed in the United States on December 1, 2021 by John

  • Excellent for my Mobile Detailing Business!
I have no issues to report! It’s excellent for my mobile detailing new low profile setup! The 40 gallon tank is the perfect size.
Reviewed in the United States on June 3, 2022 by Darron McDaniel

  • Trash
Awful and cheap. Had to pay 75 bucks to ship it back. Trash company
Reviewed in the United States on April 13, 2026 by Amazon Customer

  • Buen material
Pero hay que hacerle muchas cosas para que funcione adecuadamente
Reviewed in the United States on June 10, 2024 by Buena calidad

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