Factory video on everyone's favourite engine to hate.

[Dan LeBlanc]

Enjoy

https://youtu.be/U89CpaKojlw

[MaR]

I LOVE these kinds of videos.

[Bill Young]

Sad that these were such an eventual failure. I toured the Cadillac collection at Clark plant in 1992 and we were told that if Cadillac had not been part of GM that the HT 4100 Engine would have bankrupted Cadillac out of business.

[D.Smith]

They lost me 22 seconds into it.   "We want a lighter engine with power comparable to the 6 liter"   

[D.Smith]

Sad that these were such an eventual failure. I toured the Cadillac collection at Clark plant in 1992 and we were told that if Cadillac had not been part of GM that the HT 4100 Engine would have bankrupted Cadillac out of business.

Hindsight is always 20-20, but if Cadillac had done what Lincoln did and used a corporate engine instead of trying to reinvent one they would have kept buyers happy and not lost them to competitors.

If they had put in the 5.0 as the base engine with the 5.7 as a performance option in the 82-85 cars they would be remembered fondly.   

[TJ Hopland]

You have to wonder how different it would have been if they had had more time keep developing it and if it started out in the smaller cars as intended.   The transverse ones didn't seem to be as bad and by the time of the 4.9 it seemed to be a pretty decent motor.  It did seem odd that they kept things like the distributor.   

[MaR]

You have to wonder how different it would have been if they had had more time keep developing it and if it started out in the smaller cars as intended.   The transverse ones didn't seem to be as bad and by the time of the 4.9 it seemed to be a pretty decent motor.  It did seem odd that they kept things like the distributor.

It's the same story with the Cimarron. If Cadillac would have had enough time to incorporate it properly, it would not have been the flop that it was

[TJ Hopland]

What if they put the 4100 in the Cimmaron?  Could have been the fastest car in 83. 

[35-709]

What if they put the 4100 in the Cimmaron?  Could have been the fastest car in 83.

  Yes, but only for a little while --- until the 4100 cratered!

[Scot Minesinger]

My Grandmother's 1982 SDV 4100 powered Cadillac was terrible.  Cadillac linked the throttle so that at about a 1/3 of gas pedal travel down it was near full throttle.  To the older crowd that never drove them fast and just around town, such as my Grandmother, she considered it responsive.  To me who drove it in 1982 when brand new on the highway it is easy to understand why Cadillac declined in the future.  Also, the car was in my family for over ten years and drove only 30k miles with no issues.  My Dad inherited the Cadillac in 1991 with 20k miles and sold in 1992 because it was so terrible to drive in the low mountains of NH.  Reliability aside, the 4.1 Cadillac engine is the one I love to hate.

[cadillacmike68]

All that for an engine that was doomed to be a failure.....

I do like the chromed one in the beginning. 

Ahhh Chrome...

[James Landi]

I gave up my trusty 77 and two 78's sedans for three 4100 HT's (hook and tow).  Loved the look and interiors of the early 80's Cadillacs, but over time, realized that getting where you wanted to go on long highway drives up from FLorida was an adventure that sometimes was interrupted with "flat bed" towing and non scheduled major repairs on interstate 95 where local Cadillac service would install blown radiators, hoses, and pumps.  These engines could not keep up with traffic on hills, especially if you had any kind of load or HEADWIND, and then they'd overheat.  I did keep one 4100 running for 317,000 miles. Never pushed it to passing gear, and always ran it in Florida, except at then end of its life--- moved to Maryland and the engine shortly develop the "death rattle."  James

[Cadman-iac]

We used to call them the " Hard Times" 4100. Never saw one that was worth keeping.
They remind me of the 267 small block that Chevy had in the early 80's. But they learned just a little faster and only used it for three years.

[76eldo]

I can’t understand why they didn’t make the entire engine out of aluminum.
The aluminum block with cast iron heads made no sense.

And to make a sealing powder a mandatory additive was a real disgrace to the brand.

We had his and hers Eldorados in the late 80’s.
My wife had an 84 Eldo decked out with wire wheels, Vogues, RR grill and shell, and a roadster top with a sunroof!  Mine was an 85 Biarritz convertible which I still have stored away. Both ran great and we put over 100,000 miles on each with no engine issues. The power was acceptable at the time and in the context of 1980’s Cadillacs.

I guess the maintenance was one factor as both of the cars were purchased used but from the original owners. One owner cars seem to be maintained better.

I guess we got lucky.

[Cadman-iac]

And to make a sealing powder a mandatory additive was a real disgrace to the brand.

Yeah, those were lovingly referred to as "horse pills" and every car with a 4.1, 4.5, or the 4.9 got them whenever it came in for a service.

We could always tell when a customer didn't maintain the car when "chocolate " was draining from the radiator and oil pan.

[Eric DeVirgilis CLC# 8621]

All Cadillac needed to do was keep the 6.0 liter after 1981 and put the money into designing a quality OD transmission. That would have done more to improve fuel economy than adapting this underpowered V8 to a car it was never originally intended to be used in while continuing R & D of aluminum engines.

Of course price volatility in the energy market at the time played a role in making GM (and others) do some silly things, not to mention ever stringent CAFE regs which probably played the dominant role in the some of the more serious QC issues beginning in the '80s.   

[MaR]

All Cadillac needed to do was keep the 6.0 liter after 1981 and put the money into designing a quality OD transmission. That would have done more to improve fuel economy than adapting this underpowered V8 to a car it was never originally intended to be used in while continuing R & D of aluminum engines.

Of course price volatility in the energy market at the time played a role in making GM (and others) do some silly things, not to mention ever stringent CAFE regs which probably played the dominant role in the some of the more serious QC issues beginning in the '80s.

I agree. The 6.0 was not that heavy of a platform and like you said, with a good OD transmission and possibly a modern fuel injection system, it could have made a fine platform for many more years.

[Big Apple Caddy]

As far as engines go, I think Cadillac's decline was multifaceted.  The Olds diesels put the first kink in the armor and then there were the V8-6-4/HT4100 issues but Cadillac may have been fine if the Northstar had turned out a bit better.  Average annual U.S. sales in the 1970s and 80s were fairly similar (around 278k in the 1970s and 271k in the 1980s) but it was the 1990s when things notably changed and average sales for the decade fell below 200k.  New premium/luxury competition from the likes of Acura, Infiniti and Lexus also contributed as GM's midrange/premium brands Buick and especially Oldsmobile also saw significant sales decline in the 1990s.

[TJ Hopland]

Even if the 8-6-4 worked better than it did I wonder how long it could have lasted.  Those de bored engines typically were not especially efficient which usually meant not very good emissions so even if the public liked them from the cooperate standpoint I'm sure they knew it wasn't going to last.   You got to wonder why they didn't put more into the Oldsmobile line for the big cars?  You would think they had to have built and tested some DEFI Olds 350's and the 307 came out about the same time and turned out to be a decent for efficiency, emissions, and reliability.  Many of its issue were carb related so a Cadillac exclusive DEFI version of that maybe with dual exhaust?  That with an OD locking converter would have been a good combo.  How about if they brought back the switch pitch?

You also have to wonder when did they seriously start working on the 8-6-4? was it mostly designed in the early 70's but they were waiting for the computers to me more practical?  Because it was designed back then is why it went on the Cadillac motor instead of the Olds?   For that matter how far back did the 4100 concept go back?  You would assume Cadillac didn't really look at it back when others were doing small aluminum engines because they didn't have any small cars but what if that too was a fairly old design that just sat?  Was that maybe the original engine concept for what became the Seville?  So maybe the Seville's Olds was already a sign that they just gave up so they were not going to repeat that again in the early 80's?  "we are finally going to build our new engine ready or not'?

I'm sure the rather sudden failure of the diesel was a big factor.  81 or 82 was the peak for those in spite of the issues the early units had.  The growth in those early years was significant but not quite as impressive as how fast they fell.   I would imagine they were counting on continued growth of the diesels as part of the whole cooperate emissions and fuel economy plan.  I suppose they thought they were safe not 'putting all the eggs in one basket' meaning counting on just the diesel or the 8-6-4 or the downsized cars but pretty much everything failed in one way or another.  Kinda amazing they or any of the other American manufacturers survived. 

[cadillacmike68]

All Cadillac needed to do was keep the 6.0 liter after 1981 and put the money into designing a quality OD transmission. That would have done more to improve fuel economy than adapting this underpowered V8 to a car it was never originally intended to be used in while continuing R & D of aluminum engines.

Of course price volatility in the energy market at the time played a role in making GM (and others) do some silly things, not to mention ever stringent CAFE regs which probably played the dominant role in the some of the more serious QC issues beginning in the '80s. 

Yup. My feelings for over 30 years. an OD would have helped immensely with fuel economy. Instead GM allowed the dual strangulation ropes of emissions and fuel economy to nearly destroy the Cadillac brand.