Manufacturer's design shortcuts

What are some typical manufacturer shortcuts used to decrease the cost to build their vehicles, but which sometimes cause problems for the car owner later?

Water pump blades made of a material that doesn’t hold up, eventually degrades, and causes the water pump to spin ok, but doesn’t move the coolant?

Given oil change frequency… putting the filter in a difficult to access spot that splashes all over frame members when removed. And drain plugs that do the same!

Cars with 20 fasteners to remove belly pans to access those filters and drain plugs.

Quick connect plastic hose fittings that leak or become brittle when you go to repair them. Same for any plastic engine part…

Fuel pumps with no access panel so the tank need be dropped to change them.

Brake lines positioned so that salty ice packs in.

Almost any crimped closed component that makes it unserviceable.


This is what I was going to say. Quick connects are great for the assembly line, but a pain in the rear, sometimes prone to failure, and usually require a special tool to remove.

The plastic heater core hose elbows on the GM 3.8 liter is a great example of somewhere that it probably wasn’t ideal long term to use plastic.

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Plastic intake manifolds that becom brittle and crack with age. Gm was famous for not using a stud and nut if they could use a bolt, not using nuts and bolts it they could use a rivet and not using a rivit if they could use glue. I also remember the poured plastic retainer on GM U-joints that you has to break apart tor rebuild the u-joints and how much more the rebuild kits then cost. GMs worst money saving idea was those lousy side terminal battery connections.

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My 98 Pathfinder had a splash guard. But only 10 bolts. After a few years I took the splashguard. Cut a small section out and attached a Stainless Steel hinge and latch. Then reattached the part I cut out. Made the oil change a lot simpler.


I worked with a guy whose VW Fox (do you remember those Brazilian-made models?) needed to have the heater core replaced after just 4 years. His mechanic gave him an estimate that had to be upped quite a bit when it turned out that–unlike German-made VWs-- the heater core was riveted into place, rather than using bolts.

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My Mustang only require 3 10mm bolts be removed to access the filter… But it dribbles all over a frame rail making a bit of a mess. The drain plug is open.

The Audi requires 6 or 8 (can’t remember) 1/4 turn captured fasteners be removed. They LOOK like Phillips head screws… but aren’t. Oil change techs, from what I read, tend to break and/or lose them when they hit them with power drivers. They cost $35 a set… the only way to buy them… I had to buy a set because 3 of mine were missing when we bought the car.

If you’re interested in this from the inside, read “Car Guys vs. Bean Counters” by Bob Lutz, former GM exec. A constant battle between the two.


It’s called free rustproofing. :upside_down_face:


Because manufacturers don’t WANT the bolts to fall out and the bolts are typically zinc plated for corrosion protection

What would you prefer? Steel (so impacts will injure you)? Leather (that is still backed by plastics)? Wood (so the impacts can splinter and impale you)?

So you don’t SEE any fasteners. Fasteners are considered ugly.

All brake rotors have some extra material. Shops don’t turn them because it is more cost effective to replace them because they are cheap to buy new.

No manufacturer does this anymore and haven’t for 40+ years. Rockers and frames are galvanized, sometimes on both sides, and many are hot dipped in a paint bath to protect them.

Rubber quality today is FAR better than stuff used prior to the 1980s and lasts far longer. The same can be said of plastics.

The charging is controlled by the ECU which also has temperature inputs from outside, the intake air, coolant and more. Batteries die in the south because engine compartments are FULL and therefore very HOT. My trunk mounted battery lasted 7 years on my Florida car.

My GM truck has one.

The CD is a dead player in the music business as are cassettes, 8-tracks and 45 records. Sorry, that is just the way it is Grandpa! :smiley:

Huh? My single-line pressure system has a pressure measurement port plus the quick-connect lines pop off easily. Just how many times has this affected you?

Manufacturers use the best they can buy and my experience with them is far better lately than my 60s ad 70s cars. The transmission must come to replace a rear main and that will be expensive no matter what you do.

Nope. Very rare to have a towable automatic.

I have one in 2 of my 3 cars. That’s a majority.

So do 2 of my 3 cars… that’s another majority!

Every transmission has a filler port of some sort. If you are bemoaning the lack of a dipstick, that is a separate argument.

So what about the oil pickup screen? And what about the oil filter itself? BOTH are between the turbo outlet which goes straight to the pan and the oil pressure galleries.

Again, get with it Grandpa.

My 18 year old truck’s switches work fine… and they’ve been exposed to lots of dirt.


Yet again the SNOWMAN has to be off his meds to be spouting this \\ BS /// :upside_down_face:


Chevy was happy when they went from 2-piece to 1-piece for the rear bumper cover on the Corvette…in 1975. I don’t think anyone is going to go backwards 47 years in how they make things.


Good examples, better if each came with an associated manufacturer. I’m seeing GM, Nissan, Audi, and VW in what seems a disproportionate amount in the above listings. Does that imply this sort of problem is less in Toyotas, Hondas, Mazdas, & Ford?

As far as exposed fasteners, that’s not a problem from my point of view. Mytruck has exposed fasteners in the cabin, even on the dashboard, causes no problems for me, & makes it easier to service. Unfortunately this doesn’t apply to the door panels, which use hidden plastic fasteners, most of which have broken off.

how about a lack of a spare tire. I get the reasoning of saving weight and improving storage space and MPG, but that one is just dumb. What really gets me is that the last few International Heavy Duty trucks I have got at work have come with a spare wheel, but no tire on it!


Which manufacturer’s use the type of water pump that the impellers slowly erode? I’ve never noticed that problem on my Toyota or Ford truck. I don’t recall seeing it on my prior VW Rabbit either.

I still have the Automatic Radio 8 track unit and some 8 tracks (Van Halen, Humble Pie, and a handful of Creedence of course) that was in my Roadrunner a long time ago. Not so bad other than a track change in the middle of HP’s Don’t Need No Doctor…an adrenaline boost tune with one of my favorite bassists; Greg Ridley.

As for shortcuts; they all do it. The preferred requirement is that it lasts long enough for the warranty to expire and which is generally successful.

Subaru’s plastic govenor drive gear in an automatic trans which required R & R and complete teardown to replace is one. It only took them 4 years to figure out that was a problem before making that gear out of steel.
The downside of the new steel gear was that they started making the DRIVEN gear out of plastic so it stripped out in reverse. At least that was a simple fix.
And the replacement for the plastic driven gear was made of steel instead of installing the steel gear to begin with.

Or VW diesels using a 50 amp glow plug fuse while the glow plugs had a steady 40 amp pull with an 80 amp surge. Not hard to see where the no-start complaints come from.

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Some BMWs had it:
11517527799 - Water Pump - M50/M52 With Composite Impeller (Original BMW) | Turner Motorsport


My 1970’s VW Rabbit’s electrical system —this seemed surprising to me at the time – but it definitely seemed a little under-designed. It developed a problem handling the amount of current the fuel pump required for example, damaging the circuit plates, & requiring replacing the fuse box. The symptom was the engine would stop running for no apparent reason, usually while driving on the freeway. Waiting 20 minutes on the side of the road would often return it to a runner. This apparently wasn’t an unusual problem for the Rabbit, as I recall the replacement parts & labor were covered under a special warranty.

Yeah, those water pump impellers are definitely a problem. The ones I hear about though were made of stamped steel, where the better design was some sort of cast iron.

One problem with that sort of failure mode is it isn’t obvious what’s causing the overheating.

when I was in high school, my mom’s '89 firebird had to have the water pump replaced (twice, I believe,)because the plastic impeller broke. Not sure if “eroded” is the right word, but it was definitely heat cracked causing it to not spin internally anymore.

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