rebuild 302 or swap in 351?

[Steve]

When I was a tech, the Ford 4.6 and 5.4 motors were solid as it gets. I honestly don't remember my shop ever getting into one and many we saw were north of 200k. Now, the truck surrounding them often was a different story.

I wouldn't buy a new Ford unless it is an F250 and up with the 6.7 powerstroke. All of the turbo engines are just terrible reliability. Bad head gaskets, bad blocks on the 2.0 and 1.5

 

[FergusonTO35]

The Super Duty seems to be held to a higher standard than its light duty stablemates. I'm sure FoMoCo realizes that Toyota and Nissan would love to take over their spot in the vocational truck market.

 

[wap13]

I'm a huge fan of the 300 and it is a great engine which is why I chose to keep it in my truck instead of a v8 swap. I just think it is over hyped by lots of people that have never owned one or drivin one enough to get a good feel for the engine.

Not the first time I have seen a statement like this.

Makes sense though as you said, back in the day 100k on a vehicle and it was getting long in the tooth or used up completely.

 

[Tim N]

Back in the day you didn't have 5 or 6 speed transmissions. Engines were turning alot more rpm going down the road. That's a big reason why they only lasted a 100 thousand

 

[Steve]

Back in the day you didn't have 5 or 6 speed transmissions. Engines were turning alot more rpm going down the road. That's a big reason why they only lasted a 100 thousand

I don't think that is a major contributing factor.
Poor metallurgy and poor fuel control and poor engine design. Carbs waste a lot of fuel for the commoner and dilute engine oil. Speed limits where also slower so overdrives were not needed. Tall finial drives kept rpms around the same as newer cars of today at comparable speed limits. A lot of new cars on the road spin high rpms at cruise speed and still go over 200k with no oil on the dipstick and 3 oil changes it's entire life.

 

[Tim N]

Well I never saw any trucks from the 70s that turned 1600 rpm at cruising speed like my 2003 Silverado. Most were well over 2000 rpm. I owned many of them

 

[Al Smith]

Talking old truck engines with Ford they were slightly different than car engines .Inserted valves, steel crank shafts and forged pistons to name a few .The 390 V8 and 300 six most likely are the better if given a choice for a long life engine .A 302 is a punched out 289 better suited for a Mustang not a truck engine .It was misused on full sized Lincolns .Half ton light duty used pick ups probably okay .Not so much on heavy 3/4 or ton trucks under heavy use . I've got a 77 F250 with a 300 and 263 thousand miles .It still runs but it's been rode hard and put away wet and needs a rebuild . It's just plain tired .

 

[stretch5881]

I don't think that is a major contributing factor.
Poor metallurgy and poor fuel control and poor engine design. Carbs waste a lot of fuel for the commoner and dilute engine oil. Speed limits where also slower so overdrives were not needed. Tall finial drives kept rpms around the same as newer cars of today at comparable speed limits. A lot of new cars on the road spin high rpms at cruise speed and still go over 200k with no oil on the dipstick and 3 oil changes it's entire life.

You are a smart man Steve, but too young to remember the days of 6 cylinder and small blocks that were low geared. Some even had 2 speed transmissions. Low end grunt, but, turning 2600 to 3200 at 70mph. 3 and 4 speed trucks were no different. Bigger cars with bigger engines were higher geared. Luxury cars with same rear gears had transmissions that were geared different too.
Tighter tolerances and way better oil today, helps with engine longevity.
EPA getting involved and manufacturers making bad decisions did not help. Smokey Yunick and Maurice Petty should have been an engineer.
Yes, I am that old.

 

[Al Smith]

Might sound funny but I've got a couple coffee cans full of inserts for 429 Fords which is the exact size for Cat early D4.I've got three of them .Right place ,right time .Thus goes the life of a dumpster diver .
A lot of people don't know but a 460 was a light duty truck engine and a 370 and 429 were heavy truck engines .They put these things in concrete trucks . They really loved gasoline too .

 

[stretch5881]

Might sound funny but I've got a couple coffee cans full of inserts for 429 Fords which is the exact size for Cat early D4.I've got three of them .Right place ,right time .Thus goes the life of a dumpster diver .
A lot of people don't know but a 460 was a light duty truck engine and a 370 and 429 were heavy truck engines .They put these things in concrete trucks . They really loved gasoline too .

If I can remember correctly, 460 took the place of the 429. 429 had a light duty version for cars, and the industrial version, that looked the same at a glance, but were quite different.

 

[Steve]

Well I never saw any trucks from the 70s that turned 1600 rpm at cruising speed like my 2003 Silverado. Most were well over 2000 rpm. I owned many of them

All I'm saying is there is more to it than high rpm. But yes, the higher the sustained rpm the quicker it will wear absolutely.

 

[Steve]

You are a smart man Steve, but too young to remember the days of 6 cylinder and small blocks that were low geared. Some even had 2 speed transmissions. Low end grunt, but, turning 2600 to 3200 at 70mph. 3 and 4 speed trucks were no different. Bigger cars with bigger engines were higher geared. Luxury cars with same rear gears had transmissions that were geared different too.
Tighter tolerances and way better oil today, helps with engine longevity.
EPA getting involved and manufacturers making bad decisions did not help. Smokey Yunick and Maurice Petty should have been an engineer.
Yes, I am that old.

Thanks! And you are right too. I am too young to have experienced the way of the wear on old vehicles. Most long term experience I have with daily driving old technology is my f150 with the 300.

Actually taking it on a cross country trip here in a month or so. It should be a good time!

 

[Maintenance Chief]

I've never had a 300 spit a spark plug out under load? I'm not even a mechanic by trade and I've fixed triton cylinder heads.
I have seen a 250cid ford strait 6 keep driving with a fist sized hole in the block!
I do think gasket material has really improved over the last 50 years , metallurgy not so much , if you've ever seen the high nickel blocks of the 60s and 70s wire wheeled they shine!
Mazda and ford removed the cam keys in favor of variable value timing and used diamond encrusted washers to hold everything in place? ( on a TURBO MOTOR!)I will never figure out why, had too many of those valves not touching enough pistons?
The late model fuel injection 300 is probably the best of both worlds but I guess it depends on perspective.

 

[Steve]

I've never had a 300 spit a spark plug out under load? I'm not even a mechanic by trade and I've fixed triton cylinder heads.

Of the probably thousands of tritons I have serviced, I know I have had under 20 that had blown out a spark plug. They also break timing chain guides around 250-300k. They are noisy as hell but keep on trucking!

if you've ever seen the high nickel blocks of the 60s and 70s wire wheeled they shine!

Don't doubt they do. But there is more to an engine than a block. Bearing, piston ring, and machining technology has come a long way since then too. A lot of manufactures have been using aluminum bearings for some time now.

Mazda and ford removed the cam keys in favor of variable value timing and used diamond encrusted washers to hold everything in place? ( on a TURBO MOTOR!)I will never figure out why, had too many of those valves not touching enough pistons?

No diamond washers. Just a bolt. They do that so when you set up the valve train it is aligned perfect. Lock the cam and crank in position and torque to spec. With keys your timing can still be off quite a bit. No keys means exact timing everytime. No marks to mis align. This has been on nearly every single Ford and and Mazda 4 cylinder engine. Never had one with a slipped sprocket. GM uses this on some of their car engines. Also never had one of those slip. Only down side is if you don't have the locking tools for each engine, you can't time it.

The 3.0, 3.5, 3.7, 4.6, 5.0dohc, 5.4, 6.8 use pins instead of keys on the cams.

The late model fuel injection 300 is probably the best of both worlds but I guess it depends on perspective.

I 100% agree on this. The 94-96 was the best due to sequential fuel injection and MAF fuel control. The early fuel injection like on mine works well but with a narrow band 02 sensor and MAP sensor it easily falls out of closed loop operation and works on base fuel map. If you drive it grandma like it gets almost 18mpg because it stays in fuel control. Drive it normal and 14!

 

[Tim N]

The stripped spark plug holes is the main reason I wouldn't own a titon. I have seen several guys have this problem when pulling them hard. Other than that they were pretty good

 

[Steve]

The stripped spark plug holes is the main reason I wouldn't own a titon. I have seen several guys have this problem when pulling them hard. Other than that they were pretty good

I can see that. Not exactly a pleasant experience when it happens. Very quick and easy to permanently repair though.

 

[FergusonTO35]

Wasn't that problem due to a smaller thread diameter spark plug that they went to? Small diameter thread + aluminum head would be pretty easy to strip, especially for a Mountain Dew fueled flat rate tech using an 80 foot pound air ratchet.

 

[Steve]

Wasn't that problem due to a smaller thread diameter spark plug that they went to? Small diameter thread + aluminum head would be pretty easy to strip, especially for a Mountain Dew fueled flat rate tech using an 80 foot pound air ratchet.

Less threads and undertorque. They are standard 14mm 3/4" reach plugs. But the hole only had threads on the bottom half. Worked great on the iron heads for years but not so much on the aluminum. Like @Maintenance Chief and @Tim N said, when pulling hard the heads would expand and the plugs would come "loose" and the combustion gases would leak around the threads and soften the aluminum threads. High cylinder pressures did the rest!

 

[FergusonTO35]

A lot of people don't know but a 460 was a light duty truck engine and a 370 and 429 were heavy truck engines .They put these things in concrete trucks . They really loved gasoline too .

They were about the same performance as their light duty counterparts but the components were beefed up to withstand heavy use. Bigger water pump/radiator/oil pan/bearings and sodium cooled exhaust valves. The original Ford Super Duty 401/477/534 engines were likely the ultimate evolution of HD gas truck engines. They were super big blocks and usually checked in at well over 1000 pounds fully dressed. IHC made some big gassers too such as the 549, and GMC combined two 351 V6's to make the 702 CID Twin Six. Mack made a straight six with a cool 700+ cubes. The latter one doesn't really count though, as it was just a spark version of the diesel Thermodyne (I think that's the one).

 

[Al Smith]

It most likely has nothing to do with Ford V8's but my dad was involved was the 460's .I saw the very first of them that passed the extended dyno durability tests prior to production in dads office during the time I was in the navy .Later in life I worked and retired from that engine plant .The last of them, three has my name on them and I saw the very last one loaded into the box car . They'd run almost forever unless they ran out of oil .