overview
Building a 4x4 van is an adventure. It's an excellent way to get to know your vehicle and it's comforting to know exactly how your rig was assembled. We cater to DIY enthusiasts and support two vehicle models: the Ford E-Series (1975-current) and the GM/Chevy G-Series Van (2003-current). These body-on-frame vans are ideal for 4-wheel conversions due to their truck-like frames and ultra-durable design. Below, you'll find helpful information on how to use our site, details on the two platforms we support, and useful frameworks for designing and executing your 4x4 conversion.
this is overwhelming
Can you do this for me?
Yes- If you have a general idea on what you want for your conversion or have bought from us before and don't want to wade through all the details, just call us and we'll answer your questions and help you make good decisions. We can explain the process over the phone, put together a build/order PDF for you that shows all the parts you can buy from us and what else you need, and you can pay over the phone or by email link and not look back. Our phone number is 720.515.5933.
No - We don't handle any in-house installations. We have worked with quite a few companies around the country that can handle our installs if you need a recommendation. Some travel may be involved. The conversion labor is standardized work and we're happy to chat with your builder before you commit.
Where do I start?
You can start the process at any point that suits you. Everyone has different knowledge and needs, but the general road-map for our system is as follows:
- Crash Course - If you're brand new to vanning or the idea of a 4x4 van, this page has good coverage on the different brands, types of suspension, helpful tips on picking out a van, and general refreshers on what your options are out there.
- How-To - You're on this page! Here you can get details on the pros/cons of each of the platforms we support, some budgeting support, instructions, and helpful sourcing links.
- FAQ - If you have already have a van to convert, these are questions you'll have, so take 2 minutes and get the answers out of the way.
- Design - We've pulled together parts lists for our conversions and neatly organized options for you to design your optimum budget/performance mix.
- Order - After you've figured out what you need, purchase your kit or A'la carte your cart through our filtered parts system.
- Build - After you've paid for the parts you need from us, take your remaining build sheet(s) and locate the remaining components required to spin your wheels.
platform ford vs. gm
Overview
The Ford Econoline and GM Express vans are very similar vehicles. They are very well built body-on-frame designs with similar proportions, weights, features, and costs. These vans are both well tested platforms that have survived ages by automotive standards with relatively few changes. The standard Econoline van (passenger or cargo) ceased production in 2014, but the cab/chassis variant lives on in RV's and Buses with updated drivetrains. The GM full size van is still produced to this day and hopefully has at least a few years left. Both of these vans are ubiquitous in the US and an excellent platform for four wheel drive.
You'll find people in both camps about which van is better, so we'll try to keep things as objective as possible based on our years of selling and building both 2WD and 4x4 vans. (We built 4x4 vans for 5 years as a commercial truck/van dealer prior to selling any Timberline branded products.)
Ford Notable
- Minimum 4" lift (31-33" tire), most common 5" (33-35" tire), optional 6" (35"+ or high offset wheel)
- 8" lift available on coilover or coil spring design, high steering recommended. (37"-38" Tire)
- Solid axle design, widely available F-series Superduty front end, big brakes, simplicity, extremely durable
- Bolt-in (no-weld) options (for most vans) [does not include fuel tank mods or exhaust]
- A common conversion can be done for $12k or so in parts, some vans cost less, some vans cost more
- Some vans require transmission removal to convert, some vans require exhaust work which can be farmed out easily
GM Notable
- Minimum 0" lift (29/30" tire), most common 2" (31.5" tire), optional 5/6" (33" tire comfortably)
- Independent front suspension design, torsion bar suspension in most cases
- A common conversion can be done for $8-10k or so in parts, some vans cost less, some vans cost more
- Conversion requires some automotive experience and light fab (or a friend who can help)
- Transmission adapters are bolt-in/bolt up and do not require removal of transmissions
- No fuel tank modifications required (short vans require evap relocate)
- Vans still in production today.
Ford Pros / Cons
Pros
- Extremely durable solid axle design (4x4), handles articulation well and maintains traction / durability in tough situations, inexpensive wear parts.
- The platform is very common, so finding one to start with isn't too difficult, new parts available at most any auto parts store, used parts in nearly every US junkyard, extensive aftermarket support.
- Every part of these vans (except diesel engine) is easy to work on. Everything on the body, interior, under-hood, under-body, is modular and access is generally good. Simplicity makes them ideal for long-term ownership.
- Easy to drive and work on, popular among all ages and sexes. You'll meet people every time you drive it.
- Abysmal fuel economy almost unavoidable which even 2-wheel-drive vans have, often underpowered if geared incorrectly for usage.
- Sliding door vans require additional mod to clear rear tire.
- Solid axle coil spring vans require upkeep just like a Superduty or Dodge pickup. Ownership requires monitoring condition of joints, steering, alignment, shocks, and tire condition for peak performance.
- 4.6 V8 - suitable for light duty builds, beach vans, people movers, and lower altitudes. Not ideal for towing, but can be geared low (4.30/4.56) to be useful for many people.
- 5.4 V8 - excellent with 4.10/4.30 gearing and 33" tires, good all-around camper van engine. Not ideal for heavy towing, builds over 9,000lbs, exceptions can be made.
- 6.8 V10 - gearing really dictates the performance, V10s will tow well when geared down, but are often severely underpowered with 3.73 gears despite very high torque numbers. 5r110/6r140 transmissions accompanying the 6.8 are more desireable.
- 7.3 diesel - the favorite of most Ford van people, these engines are noisy and leaky and old, but score very high on the power/economy/longevity scale. They are ideal for towing, for heavy rigs, and for people who are racking up tons of mileage.
- 6.0 diesel - again, very noisy, incredibly so when cold, durable when well kept and serviced, but finicky about service so be careful if you don't know the history. These vans can stretch head bolts when tuned and there are unpopular peripheral issues (oil cooler/egr cooler, sand-cast-heads,VGT issues, etc.). The engine is difficult to work on in the small space. A perfectly tuned 6.0 with an insulated cab is superb but you need to know how to work on it.
- 6.2 V8 - this engine had a short run in E-series cutaway/chassis vans. It is a 2 valve motor and very similar to the V10, likely extremely durable without the variable valve timing, and paired with the 6r140 it hauls well.
- 7.3 gas - this newer engine referred to as "Godzilla" is a very popular motor and reported to be extremely durable. Ford did away with the problematic 3-valve engines used in trucks, so this is a simple design. Users report similar gearing considerations that we have above with the V10. Ideally, heavy rigs with this engine should opt for 4.10,4.30 or 4.56 gearing.
GM Pros / Cons
Pros
Engines
- IFS suspension is much nicer to drive on rough roads and long trips compared to most solid-axle conversions.
- Standard lift (0-2") 4x4 conversions will drive nearly indistinguishably to a standard 2-wheel-drive van.
- Fuel + Power - LS engine architecture found in most vans is univerally regarded as the capstone of US IC engines. They achieve better fuel economy, more power, and are equally durable if not moreso than the comparable Ford offerings.
- Some early express vans, such as 2003-2009 with gas engines can be relatively inexpensive to convert, like under $6000 territory if you have access to affordable used components. Most standard lift 4x4 conversions cost less to execute than comparable E-series, labor is probably similar overall and varies just like it does on Fords.
- The platform is very common, just like Fords, slightly fewer on the road, but they're still everywhere and so are parts both new and used.
- Modular vehicle architecture is similar to Ford, so both the vehicle and the drivetrain are relatively very easy and simple to work on.
Cons
- Extended wheel base vans without Hi-lift are both difficult to park and do not have sufficient ground clearance for fire-trail usage without skid plates.
- Barn door vans can have issues with the hinges and dings in the middle door. The floor rails in the passenger vans are awful to remove, flyaway paint is common on hoods, roofs and fenders, and it's not uncommon for people to gripe about the seat comfort level.
- 2021+ vans have locked down ECU's, so tuning for re-gears and large tires is still a bit of a grey area (as of writing this.)
- Vans with lane assist and backup sensors do not play well with aftermarket bumpers, but systems can be effectively bypassed. (at least in 2021-2022 models we've tested)
- 2.8 diesel - this engine is outstanding, returning superb fuel economy, it's relatively quiet, and not too bad to work on. It is not a powerhouse and likely not great for towing, large tires, or heavy builds. It is one of the more time consuming and expensive conversions to perform.
- 4.3 V8 - when paired with 8-speed transmission (2017+) these are surprisingly responsive, but likely not great for towing or heavy loads in the mountains. No data to provide on 2003-2009 4.3 models.
- 4.8 V8 - similarly to Ford, these need to be geared appropriately, 4.10 minimum to achieve good power, but with standard or slightly larger tires, 4.8s with 4.10s do just fine.
- 6.0 V8 - This is a common and popular engine with a great power-to-economy ratio, bomb proof design, compatability with 8.25" & 9.25" front diffs and they are easy to work on.
- 6.6 diesel - Common in buses and cutaways, this engine is heavy, has loads of power, it's much quieter than Ford diesels, but it's very difficult to work on. In most instances, the standard lift necessitates the 8.25" front diff, hi-lift vans accept the 9.25" without issue.
- 6.6 gas - Our favorite of what's available thus far overall. It has the trusted 6.0 framework, 400hp, decent fuel economy for the size/style, and paired with the newer 8-speed transmission in 2024+ vans, it will be hard to top. This engine cooperates with 8.25" diffs much better. Even hi-lift vans with the 9.25" diff require finesse to fit properly.
instructions
Do kits come with instructions?
We are routinely praised for our instruction manuals. Small kits come with printed color details and core/turnkey kits come with fully bound color manuals that have excellent photo documentation, organized details, torque specs and loads of tips.
Do you have video support?
We are working through hundreds of hours of video footage shot over a year of about 8-10 builds...slowly and hope to have that up and running soon, but no launch date is set.
Can someone answer questions mid-build?
Timberline has always been very well regarded for technical support. We do our best to get to emails as quick as possible and tend to respond quickly to text messages.
Vocal phone support is offered Monday-Friday during normal business hours on non-holidays. We do our best to answer mid-build technical questions by text evenings and Saturdays. We tend not to answer any sales or technical questions on Sundays unless it sounds like an existential chrisis.
budget & parts lists
Here you can download a couple of basic printable budget sheets to mock up for your 4x4 conversion. More specific part details are located in the Ford & GM design sections of our site. Specific part numbers are listed in build sheets you can request at the bottom of that same page.
parts sourcing
Where do I find an axle or transfer case?
Car-Part.com - We recommend car-part for finding all axle cores, t-cases, diffs and transmissions. Do your research, call the companies on the phone and if you can stay within the PRP network, those yards are typically good to deal with.
Ebay.com - eBay has limited uses for used parts. Ford axles tend to be way overpriced, but transfer cases and GM front diffs can be bought for very fair prices on occasion. If you're dealing with a shop, just be careful about the core charges they may have and only buy from people/shops with plenty of good feedback.
Facebook marketplace is a place people often seem to go. We don't really support it as a good place to buy parts unless you are extremely familiar with what you are buying. Items are often misrepresented either in quality or application, so just be careful. Prices range wildly so there are some good deals to be had.
Where should I buy wheels and what size?
Wheels - Be careful where you're buying these, eBay and individual sites mass market wheels they often don't have actual inventory for. Wherever you're buying wheels, contact the seller direct to see if the part is in stock before paying for anything. It's not a bad idea to buy wheels from your local supplier. Discount tire actually offers pretty good prices on wheels.
Wheel Sizes
Ford: Minimum 17" rims on E-series conversions. Pattern on standard vans will be 8x170mm, recommend 0 to -12 offset. Zero offset rims can be run without fender flares. Anything that sticks out more will likely require flares. Dual rear wheel vans are typically setup with 8x200 pattern (Ford) and again, 17" minimum.
GM: Standard lift vans (0-2") can run factory rims if desired. We commonly run 17" as well if you'd like a more custom look. The pattern is 8x6.5 for all GM conversion. All Hi-Lift vans require 17" rims to clear the front steering knuckle mounts.
New Part Recommendations
Rockauto.com - This is an excellent source for new parts and brand name components, searchable by application or part number. They ship quickly, generally have great inventory, and packaging gets the job done for the most part.
Fordpartsgiant.com / GMpartsgiant.com - These are great sites that source parts from nationwide dealer networks. The customer service is non existient, but the prices are good and you generally won't need help. It is also a great tool for figuring out factory part numbers.
Amazon.com - The giant is often a good place to find something if you know the exact part number you need. This is not a great place to buy things like tie-rods, ball joints, etc, do not buy cheap wear items.
Ebay.com - eBay can be hit or miss. Sometimes you can find deals on close-outs or new old stock items and resold new parts like Fox shocks. Copy-cat brand name goods that are too cheap probably aren't authentic.
Carquest / Napa / O'reilly / AutoZone / Advance Auto Parts - These are great sources for things like brakes, rotors, heavy to ship items. They often have listings for more than you'd think. They often price-match and will give you best pricing if you ask for it. Just like Amazon, don't buy the cheapest stuff, opt for the best grade in-house components they have.
Walmart.com - Fluids, shocks, wheels, tires even, Walmart has an incredibly large catalog and often offers cheap prices and free shipping. It's a great place to shop wheels and you can see what's actually in stock.
