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4/10/24 - Timberline will have limited fulfillment on core/turnkey kits for May. April has been filled. We have 2 spots in May, and further larger orders will likely ship in June when normall fulfillment continues. Smaller orders on 1-5 pieces shouldn't have too many hold ups. We appreciate your business and are working hard to keep up! 720-515-5933. Thanks!
4/10/24 - Timberline will have limited fulfillment on core/turnkey kits for May. April has been filled. We have 2 spots in May, and further larger orders will likely ship in June when normall fulfillment continues. Smaller orders on 1-5 pieces shouldn't have too many hold ups. We appreciate your business and are working hard to keep up! 720-515-5933. Thanks!
E40D / 4R100 Bolt-up 4x4 Conversion Kit

E40D / 4R100 Bolt-up 4x4 Conversion Kit

$945.00
Kit Options
Description:

This is a straightforward bolt-on solution for converting your 2-wheel drive E40D or 4R100 transmission to 4x4 without the need to cut the output shaft.

To accomplish this, simply remove the 2WD extension housing, bolt up the provided OE 4x4 housing, and attach our billet aluminum adapter to your compatible 31 spline input NP271 / NV 271 transfer case.

There are some qualifications pertinent to your van and skill set you should be aware of before purchasing this.

Transfer Case Placement: The conversion pushes the transfer case about 5.5 inches further rearward compared to using the standard 4x4 extension housing. This may require significant modification or replacement of the fuel tank. Our bolt-up solution works best for Gen 3 vans with dual tanks, rear-mount tank vans like Cutaways, or projects where you are switching to an Aero Tank style rear-mount tank or similar.

Speed Signal: If the van's speed signal is obtained from the output shaft speed sensor (OSS/VSS) on the back of the 2WD transmission, an electronic ratio adapter like the Abbott ERA or the SGI-100BT units will be necessary. The 2-wheel drive extension housing speed sensor differs from the 4x4 unit. To our knowledge, it's not possible to mount a reluctor ring to the 2WD output shaft. Instead, the rear differential speed sensor can be used, but the pulse needs to be slowed down, which is achieved using the electronic ratio adapter.

Crossmember: Clearance is generally already fairly tight on some vans where the front driveshaft passes over the transmission crossmember. You may need to notch or section your crossmember to clear the front driveshaft depending on the lift size, u-joint used, or other factors. 

Fitment Designed for: 

Van Side - Gen 3 and Gen 4 E-series vans with AOD, E40D, and 4R100 Transmissions. (Verify 31 spline output with AOD vans)

Truck Side - NP271 or NV271 Transfer case with 31 spline input shaft, generally years 1999-2002, also 2003-2010 with input shaft changed to 31sp. Will work with BW1356 and may work with other units like 205, 241, etc. 

Tools Required:

Standard hand tools

Included:

Transmission adapter assembly, 4x4 extension housing (optional), M10 grade 10 studs, toplock nuts, thread locker, electronic ratio adapter (optional), Grade 10 M10 bolts.

Construction Notes:

Machined solid billet aluminum, Cast Iron, Grade 10/8 hardware

Tips / Skill Level:

1-10 (10 being most difficult) Level 2-4

This product may work with other model vehicles. 

Safe torque spec on all hardware is 37lb ft and please use thread locker where hardware does not have locknuts. 

Shipping, Fulfillment, Taxes, Quality, and Returns

  • Shipping: Our components are carefully wrapped & packaged and shipped via UPS, USPS, or FedEx, depending on what is available. If you require a particular carrier, please contact us ahead of your purchase.  Customers in Colorado may arrange for in-person pickup within 1-2 business days of purchase. 
  • Shipping/Fulfillment time for components: We typically ship within 1-2 business days of your order and we carefully monitor our inventory. In the event that we are unable to meet that timeframe, we will contact you and arrange either a full refund or a timeframe for fulfillment agreeable to the customer. 
  • Taxes: Colorado residents must pay a sales tax of 7.5%, no sales tax is collected on out-of-state shipments currently. 
  • Quality and Returns:  We are consistently complimented on the quality of our products and the ease of installation. Fabricated components are generally hand-built here in Colorado by seasoned professionals. Replacement or aftermarket parts are only offered in high-grade options.

    If you are in any way disappointed in the components, we will issue a full refund less the cost of shipping when the product is returned within 30 days of receipt. If you decide to return any components that didn't apply to your build or you changed your mind about, a shipping+15% restocking fee will be deducted from the refund.