OEM vs After Market

[CapelConcepts]

I've been trying to figure out how to word this question for a while now. I haven't come up with something that I felt explains my question completely, but I figure I've gotta start somewhere! Here is the general question: What is the best choice for an expedition type rig, when related to drive train and suspension (the two most important areas, imho), OEM (Original Equipment Manufacturer) or After market.

Here's my opinion: OEM for drive train and after market for the suspension. Here's my reasoning: The OEMs put 10s of thousands of hours into everything they do so it stands up for 100,000+ miles, you can get parts across the US (in most cases), simple and clean. Some may say that the same applies to the suspension, but I have my reasons for my ideas choosing aftermarket. Most stock suspension is made of very good quality parts (I did six months of leaf spring testing with one of the last companies I worked for and the stock springs surpassed the after market stuff in many ways), but it doesn't quite do what I feel it should. I love a purpose built suspension...it's an addiction! Anyone that has ridden in a truly well set up vehicle will agree...it makes a HUGE difference. This is also an area that I feel the after market and can come close to or do better than the OEMs. I feel that equipping a vehicle with a well thought out, well designed, and well executed suspension is one of the most important (and commonly over looked or underdeveloped) areas on any vehicle.

Here's some of the down sides to my choosing an after market (home/custom) made suspension: PARTS AVAILABILITY! (custom translates into can't find it at any store!). I feel this can be overcome by choosing quality parts, designing in failure points, and carrying spares for those points.

I appreciate you all letting me get this question out there and I really look forward to hearing your opinions on the matter (especially when based on experience....I love internet wheelers as much as the next guy, but please keep the "...I read on the internet..." to a minimum).

BTW: I put this thread in this section because the next rig I'm looking at build will be closest to an American full size.

 

[Sportsman Matt]

Biggest thing is how deep are your pockets? Reasoning the cost of converting a rig may be beyond what some folks would think of. I only plan on doing a couple upgrades to my truck, mainly heavier springs in the front end and possibly replacing the springs in the rear with a set from a 3/4 ton GMC. I travel alot during the Spring to Fall, and found that if you build it yourself, you're going to have to figure out a way to fix it yourself, as most garages lately are only going to swap out OEM parts for OEM type parts. Very rare today is the garage that will make something or modify something to fit because of the sue happy mentality of society today.

Also you need to know every little detail of your vehicle, like when I bought parts for my old blazer, the brakes for the front were off a 85 3/4 ton K2500 with the 5.7L V8 Automatic and heavy duty brake system (even though they weren't), the brakes for the rear were off a 86 1 ton C3500 with 12" Drums (same), when buying the transmission filter I had to tell them it was for a 79 Monte Carlo with the 3 spd automatic and 305 V8 (they can't translate TH-300), and so forth. Sad thing is I would give the guy the part numbers in the old days and that would be it, now when you go in to buy a part, everyone there behind the counter needs to know what type of vehicle, how many miles you drove it, your ssn, your great grandmother's 3rd grade best friends name, a credit report from the big 3, and the last 5 addresses you lived at just to get a fuel filter.

With that said, good luck

 

[granitex1]

The OEM suspension is a compramise, to the majority of the people whom they think will buy the truck. If that compramise load/articulation/ride quality/hight, works for you than great. But if you need something else then that is the time to determine what you need. All of it is driven by what you need to do, partly picking the right truck in the first place, partly making realistic goals and expectations on that truck.

 

[ntsqd]

I have my suspicions that the aftermarket suspension stuff, as you've alluded to, does not have a MTBF rating that the OEM stuff does. So long as that is realized going in I think that it can be a fair trade-off.

I do not mind custom parts at all, but, and this is very important to me & I feel should be to everyone, all of the wear parts need to be off the shelf parts. No modified wear parts. They do not have to be for the original application, but they should be chosen for both suitability to the use and availability in the area of operation. One has to be especially on guard about using a part that was only used for a short portion of a production run.
An example of this would be the tie rod and soon to be drag link on my '84 Toyota 4wd pick-up. The wear parts are FJ80 for their availability anywhere I'm ever likely to take that truck, but the parts in between those wear parts are custom.
That said, those custom parts need to be designed and/or chosen such that they are very unlikely to ever cause a problem.

Should the development of a vehicle result in non original OE parts I highly recommend that a notebook with the original applications, and if known, OE parts numbers (or NAPA numbers if solely U.S. operation) should be a permanent part of the vehicle. Six years from now very few will remember that the rotors used on that rear disc brake swap were from an '83 Henway 1/4t lorry with the full float rear axle.

 

[DaveInDenver]

There are a couple of things in my mind that dictate OEM vs. aftermarket. Like you point out the original parts are designed to a specification and meet that spec very well. But deviate from the intended use and OEM might not still be the best part. This is true for everything on the vehicle IMO. So I tend to use OEM Toyota (or the aftermarket equivalent like Koyo, Denso, etc.) where there is no better alternative in my view. But availability also must be weighed, so even if there is a better aftermarket part, if it's rare, requires irreversible modifications to work or is very expensive, it might not justify the cost when weighing all variables. One of the major Toyota aftermarket suppliers (Marlin) offers parts like seals that are significantly better than even stock which don't require any modifications. I use them if appropriate (his inner axle seals are head and shoulders above anything on the market, OEM or not). Same with his transfer case output seal. I use these parts, but I can use a NAPA or Toyota part in a pinch. His transfer case gears and bearings (he uses the same OE manufacturer to his improved design, for example) are also as good or better than OEM, so rebuilding a case with his parts and expect higher reliability.

That said, I don't run a completely stock engine, drivetrain or anything. Same with suspension.

Toyota or any other manufacturer designed that truck to meet power, emissions and efficiency requirements that either/or the market or government imposed. I personally am willing to give up some fuel economy for a bit more power if reliability is not impacted. In the case of my 22R-E reliability is expecting 200K miles from an engine at ~18 MPG producing 125HP. Lots of people achieve 250K or 300K easily with a completely stock engine. But Toyota left around 25% of the power on the table for the taking with relatively easy engine changes. And Toyota's 22R long block has one fatal design error, the timing only lasts about 125K miles before you risk breaking the chain guides, which can be catastrophic if left unattended. So there are options to beef up the timing with aftermarket parts, but they are still a wear item and so replacement might be necessary. So I run the best factory style part (which is actually the Toyota part) and follow a periodic replacement. I also use a factory head gasket, but run a modified head that uses non-factory valves and a cam. Those things take decades to wear out and so I am not concerned with sudden failure, but do like the bit of extra oompf I get.

Suspension is rarely designed from the factory to take the beating and constant loads you use driving off highway. They are designed to be safe for the GVW, but not necessarily comfortable. I think rolling your own suspension is paramount to customizing the truck to your use.

Also remember that the manufacturer also is constrained by price and cost. If making the suspension stronger for overland use means each unit costs $500 more, that might mean the other 90% of the people who just drive them on the roads will balk at the price. So most companies offer upgrades as options or simply just ignore the market. Same with engines, if the truck has a better power curve for off highway it might be slow on the pavement (i.e. most Toyota trucks before 1995!). So the market trends towards the high power V6 because it test drives better at the dealer, while the slightly bumped I4 might actually better fit your use.

Another sore spot in my view is stock gearing, manufacturers put much too tall gears in their trucks. Overland type use requires the option of real reduction in the drivetrain. From the factory you are lucky if your low/low is 35:1 or 40:1, which is just too high to really control a heavy truck in technical terrain. I think some or all of 4.xx:1 level diff gears, 4ish:1 first gears or 3~5:1 transfer low range is needed and that's almost always going to require a third party supplier.

I'm a dyed in the wool Toyota person and default to the OEM part, but if a part is shown by either design or testing to be better, I'll consider it an upgrade. Toyota builds good cars, but they also can't make the ideal vehicle for all uses. So I don't think running Ted Stanwood's head or Marlin drivetrains is anything but an upgrade for what I do with my truck.

 

[UK4X4]

Engine / gearbox / transfer OEM...

The rest well half oem parts come from the same supplier that the napa bit does...it just costs twice as much for the box

Most wear parts you would take the spares for/ bring the oem removed bits with you.

Suspension from OME and ARB is pretty well tested.

One thing with travelling and working in the 3rd world is you really get to see
bush repairs as a fine art.

The one thing most bush mechanics have is a welder, a pile of old parts
and a large hammer

Just enough to get you to the nearest city, where most things are available and those that are'nt can be fedex'd

 

[Prybry]

Tough question...

After doing both... built a '90 YJ myself, and now owning a '05 Dodge Power Wagon which is one of only a few off-road toughened OEM rigs available.

I would lean toward the after market for one simple reason... knowledge.
When you build it yourself (not pay someone else to do it) you not only have the knowledge to fix it when you break it, but you have a better idea of what the rig can take and where the weak spots are. This goes for most any part on the truck, drive train, suspension, what have you.

Don't get me wrong, I love my Dodge PW, but I also selected it with the "knowledge" of what I needed in a off-road trail truck.

After you've built, broken and built again, you have the "knowledge" to make smart choices on OEM or after market components.

 

[pete.wilson]

Hey

The first question should answered most honestly by yourself is "what do I want my vehicle to do and what is the best way to achieve that taking into account possible design changes, any warranties that may be broken, common failure point of your vehicle, if an older vehicle and install new part...what of the old surrounding parts going bad, which manufacturer has the best base vehicle on which to build.

Like you mentioned; most OEM do farely well in the engine, transmissions, even transfer cases to an extent, and cooling system are rather robust for most off-road. Next would be the incorporation of stronger Axles and more importantly the addition of lockers front and rear. Stronger driveshafts (etc) and their U-joints.

Suspension upgrades are needed for clearance, increase in travel and generally stronger components due to the excess Tire/wheel size and amount of off-road abuse. Shocks should be the best you can afford, along with the upgrades is the need for better braking which is often overlooked, also a change in gearing front and rear so you can better map engine performance to the tire/wheel size. Learn the strong and weak points of differing types of Suspension mods. (quad link, tri-link, etc.) Not to mention not every lift kit is created equal and all have their weakneses also, but from a reputable manufacturer who may specialize in your type of vehicle as they will have the most experience and done the most research (hopefully!)

Last is the world of aftermarket performance products to cover the rest of the vehicle, logically buy what works. Again it all comes down to what you want to do with it and how much your willing to spend. Realize any short comings in your vehicle and drive it accordingly, error on the side of caution always. Maybe your stock vehicle does almost everything you want to do, then don't waste your money but spend it on going out and having fun. Always count the cost first and get the most bang for your buck first. Usually new tires. Just my thoughts, everybody else has one too.

Pete Wilson

 

[CapelConcepts]

Thanks to everyone for the responses! As I was reading them I figured out how to better word what I'm thinking. What I'm looking at is finding OEM parts on different vehicles to build a quality expedition rig. By pulling specific parts off of stock vehicles, placing your braking points in easy to fix places (like stock u-joints), and making it so you can get parts anywhere you'll get OEM quality with the modifications you want. I know it's done all the time, I'm just wondering why we don't see more of it.

 

[CapelConcepts]

I thought I'd show you guys what I was talking about with using parts from other vehicles. Here are some pics of a Bronco I'm building for a customer:

It's a (or was a) '77 Bronco. I've stretched it to a 122" wheel base, pushed the front end forward 2-3" and the rear back 24". The axles are out of a '79 F-150 (reverse rotation 44 up front and a 9" in the rear). The coils and upper and lower coil mounts/buckets are from a early '90s Toyota Land Cruiser. The bed is off of a late '90s Dodge, full size, long bed, fleet side truck. The seats are out of an '05 Jeep Rubicon (front buckets with the rear fold and tumble). The original plan for the Bronco was to do a full race set up with coil overs at all four corners with tubes everywhere and aluminum skins for the bed....the budget ended up getting a huge change and we still wanted to finish the project so we started scowering junk yards to see what would work for our project. This is what we've come up with and both of us (my customer and I) couldn't be happier with the way it's turning out. I'm hoping this will give some hope and/or ideas to those that think there project is out of reach!

 

[Desert Dan]

I would venture to say that a "custom fabbed hot rod" type would not make the best expedition vehicle. It would be a fun rock crawler or weekender though.

It also depends where you are traveling and how much tinkering you want to do.

I try to keep my vehicles pretty stock except suspension mods for load capacity and increased travel.

If $$ was no issue I would go for a HD off road truck that didn't need much modification to handle off road work.

 

[Root Moose]

Big fan of OEM drivelines. Simple bolt ons are ok or even stuff like a cam change. If it is just changing the shape of the torque curve versus making a ton more power and more importantly, heat. Stuff like a "mild RV cam" is fine IMO. Anything exotic, I'm not for it. Swapping in a mostly stock OEM drivetrain (say GM 5.3) into something like a SWB Jeep or LandCruiser is ok IMO. The caveat is making sure that the drivetrain is available/supported where ever you may end up driving the vehicle.

Suspension, I think that is mostly fair game. Provided you buy quality parts I wouldn't be too concerned about MTBF on the springs. Dampers, most quality aftermarket stuff is better than OEM. The proviso is that you are sourcing a suspension that is relevant for the task. For example, adding a 1/4 elliptical spring kit intended for rock crawling on an expedition style rig is likely a bad combination. Spooky handling at the limit anyone?

IMO, ultimately it comes down to research and knowledge. It is something that you need to be intimate with and understand the ramifications and limitations of making the changes.

 

[dzzz]

OEM's don't make suspension parts. Aftermarket suspension companies don't necessarily make suspension parts. It seems to me suspensions are one area where the best offroad type stuff comes from the aftermarket. A automotive manufacturer purchases the lightest, least expensive part that will meet the spec. The best of the aftermarket guys overbuild their components.

I think the bigger issue for suspension is the person designing the upgrade. There's no part that doesn't work as part of the system. There aren't that many really good off road suspension guys outside of western north america.

As far as engine and drive train, at least now the oem parts can be purchased on line for a discount. Selling at huge markups is what created the aftermarket business in the first place. Of course many manufacturers make parts for both OEM and aftermarket.