I'm considering buying an old army jeep, and fixing it up as a putt around town vehicle. I'm not particularly interested in a completely faithful restoration, at least as far as the internals go, but in finding a good compromise between aesthetics and street functionality.
Anyway, my main concern is with highway speeds. I read that these old jeeps have a hard time getting above 45 without blowing the engines or causing some other kind of serious trouble. What are my options for getting an army jeep up to 65MPH or so? The websites I've seen so far don't seem to be of much help.
Aside from not being designed for "around town" use, being unstable at speed, poor gas mileage, and not too safe in a crash, the MBs are wonderful and fun vehicles. Perhaps you should be looking for a 2 wheel drive DJ postal Jeep, or even a car.
Got to disagree. My '05 TJ runs 65-70mph (70 is the limit here) highway all the time here in WV, except for some of the steeper hills. But again, the 2.4. has more power than the 2.5. Mileage has been consistently between a low of 20 and a high of 24. Usually
military jeeps came with 5.38 gears in the differentials, not really happy over 45 or so although they will get up to 60 on a straight level road with a good tailwind ;) but it's hard on the engine. Really, for "putting" around town you'd be fine.
If you have to spend appreaciable time over 45 than for ~$650 or so a Warn or Saturn overdrive is the answer. With one of these you still only get 60 mph, but you can do it without the tailwind & the engine will be much happier. You rally don't want to go much faster than 60 in one of those things anyhow, that would tend to induce nervous quivers in both you & the jeep :(.
ODs are available from Herm Tilford @
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Herms a real good guy, know his stuff inside out
If you decide you need to go faster than many people go with a Buick V^ engine swap, cheap &easy.
If you arn't interested in staying "stock" or properly maintaining the stock Ross steeringsetup than a saginaw steering conversion might make sence also.
The one item I would really recommend from a safety standpoint would be upgrading the brakes to 11" drums with a dual circuit master cylinder. This also is a cheap & easy project if you can scrounge the parts.
For mare info I'd sugest perusing the Willys Tech & M38A1 groups on Yahoo as well as "The Early CJ5 &DauntlessV6"
Years back I drove a '48 MB for a couple of years. It would get up to
55-60 on the downhil sections of the Garden State Parkway if you had a tail wind, but it sounded like it was wound so tight that you didn't stay yher too long. What I remember most about it was the stability. With the short wheel base and narrow track keeping it on the road was a full time job at or above 50mph and staying in one lane was questionable, especially if there was any crosswind. Great fun when I was young and stupid but not my idea of a touring car.
Bryan, my 2000 TJ has *never* delivered better than 17, and I usually expect 14. That little engine is so anemic and the Jeep is geared so low that 70, for me, is wishful thinking. Here in West Texas the speed limit is 75, but most traffic travels between 85 and 90, and 100+ on lonely desert highways is to be expected. The only time my Jeep sees the highway (and just about the only time it sees pavement) is when it's being towed behind my RV.
Maybe it's the new 6-speed that makes the difference.
I'm just adding my two cents to this thread because maybe it will help the original poster.
I spent twenty-six years in the army with many thousands of hours in M38, M151, and other assorted vehicles, including the combat development command where we tested some strange things.
The design was for off-road, meaning that the tires (look at them) are for mud and not for high-speed, or even wet weather on asphalt. An original Jeep tire will hydroplane easily, in rain, and, if dry, will get very hot at highway speeds, since it is riding on only the center high point.
The power train, and the short wheelbase chassis, is more for pulling stumps than driving in a straight line, at any speed.
We have had more soldier accidents on highways than off-road, and a lot of the safety briefings were devoted to driving on the highway, where the driver is constantly fighting the large wheels going in every direction. Remember, the military Jeeps did not have tire balancing, front end alignments, etc. Nothing that the modern car has to have to drive in a straight line at highway speeds.
And shall I tell you about convoying Jeeps in the rain? The vacuum wipers that slow to nothing when you accelerate. The canvas top that blows up then down with a whack that makes you hold your ears. The heater - oh wait - there's no heater. The small tail lights that you only see when you are ten feet away -oops! The wonderful olive drab paint that means nobody can see you in the dark -oops!
The 6 speed helps, and the 2.4 is, IMHO, an improvement also, with more power than the 2.5 I would not want to try to keep up with traffic at the speeds you describe, and I don't think my TJ would be up to that either. But I can do 70mph fine on the interstate, with some drops to 5th gear and
60-65mph on the longer or steeper hills, or against strong headwinds. My good mileage I attribute to spending most of my time on rural roads at
45-55mph. For what it is worth, I have test driven several 2.5 Wranglers, and was put off by the poor performance, and I did not want to buy a 6 cylinder, as whatever I own must also do double duty as my daily driver. I drive a lot as part of my job, and so every mpg means a great deal. The 2.4 caught my attention, and with the addition of the 6-speed, it was time to go to the dealership and try again. I was pleased with the improvement over the 2.5/5-speeds.
Of course, I wouldn't mind a 6 cylinder Rubicon, but banks are funny about wanting their payments on time ! :-)
I used my '48 Willys for about 6 months to commute a 40 mile round trip to college. Was a fun ride, no highways. Got a lot of strange looks around campus, and should could fit in about any open parking spot. I would not recommend it but it sure was a fun ride.
My father-in-law had an old Willy's when my wife was very young. Lot's of fun memories for him (and her). He swears it would go anywhere, and won a few bets by chaining it up to some friends pick ups and seeing who could pull who ! Of course, they didn't have 4 wheels drive, either.
Our new TJ has brought back some old memories for her, and inspired new ones, as it has prompted us to take some wonderful rides in the mountains with our son.
My 1999 TJ gets 18mpg without a problem. I have the 2.5L with a 5 speed.
Also have 4" of lift and 33x12.5 BFG MTs. I get up to 60-65 without a problem. 70mph is doable without a head wind and no hills. I use 5th gear all the time too.
And yes, my speedo is dead on (replaced gear, verified with GPS). I've done a few engine mods, but nothing serious: Cold air intake, throttle body from a 4.0L, and dynomax cat-back exhaust. But the most important mod was the TB spacer! YA! (heheheh...)
Putting around town is a lot of fun in an old Jeep. I have a lot of fond memories of doing that. Lots of attention and it's just plain cool.
However - Old Army Jeep on the freeway? I personally wouldn't - that's why I'm building "Frankenwillys". There are plenty of old Jeeps and Willys that are a lot better at speed than military style Jeeps designed for pulling cannons across muddy fields.
Despite others driving fast with newer engines in various flavors of Jeeps, the original Jeeps are really narrow and there are a lot of them gone from this world because of it. Drive 70 mph in an MB in a wind and hit even a small pothole and you could find yourself flipping like a Chinese acrobat.
With the amount of mods you have to make just to make it a modern driver, there might not be much Jeep left. Not that you can't do it (I am with my Frankenwillys), just be aware that it's a VERY complicated and expensive undertaking. I'm not doing it to save money, I'm doing it because I REALLY want a Willys Wagon 4x4 that I can drive at 75 mph all day long.
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You might be better off just buying one already converted by someone else.
Cheers, - Jeff G
p.s., before I get a bunch of emails about why I haven't updated the website :: I will be soon, just finishing a couple other projects that are a higher priority ("OK honey ... Yes dear ...") The Willys is coming along pretty well, I'll get more pictures up soon - I promise! ;)
As you aren't that concerned with keeping it stock one thing you might consider is a swap that I've heard was popular years ago, replacing the little 4 cylinder with a Studebaker Champion 6. They aren't all that big, their tough, believe it or not there is a fair amount of hop up stuff available for them, and apparently they had the same bolt pattern so they will pretty much bolt right in (which is why they were a common swap in the old days).
Just found this interesting article...
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Just a thought...
Oh, and whatever you do put some modern tires on it!
Got to disagree. My '05 TJ runs 65-70mph (70 is the limit here) highway all the time here in WV, except for some of the steeper hills. But again, the 2.4. has more power than the 2.5. Mileage has been consistently between a low of 20 and a high of 24. Usually
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