Question on 70 FJ-40 drivability with 35's

[weigellj]

Looking at buying a 1970 FJ-40. The truck is setup with the old 1f motor and a 3 speed tranny/tcase. The engine has headers and a weber carb (not sure of which model weber). 4.10's in the axles, disk brake conversion. As far as I know everything is up to par on the rig as far as running/driving. Also there are no doors and no top.

Thinking of buying this as an occasional wheeler and summer driver. How bad are the 35's going to be as far as driving on the highway. I know its not going to be a corvette, just want to know if it is doable. Will it get up to and hold 55-60, until I hit a hill

 

[Shawn Russell]

I had a 72 with a stock F and 35. I think they were too much. I went back to 33 after the 35s wore out.

I now have a 70 with 35s, and a V8, and no P/S. Very drivable.

Shawn

 

[dgangle]

test drive it and see. your question is completely subjective. only you can determine if the performace is acceptable

 

[weigellj]

Its got 31's on it now.... Kinda hard to test the 35's, I don't have any... I shoulda been clear on that. Hopen someone had tried it and it worked or it didn't.

I'm thinking its going to be too much tire.

I suppose I could bolt my 38's on and take it for a spin. That should give me a good idea.

 

[rusty_tlc]

Its got 31's on it now.... Kinda hard to test the 35's, I don't have any... I shoulda been clear on that. Hopen someone had tried it and it worked or it didn't.

I'm thinking its going to be too much tire.

I suppose I could bolt my 38's on and take it for a spin. That should give me a good idea.

I occasionally ride with a guy in our club that has an F with 36's. I'm not sure what his diff gearing is. At any rate it motors over Donner summit without to much trouble. I drive a 2F with 4.11 diffs and 36" swampers (possibly one of the heaviest tires on the planet) I do a lot of shifting on grades but it will cruise 55 to 60 on flat ground. It could go faster but I get skeered with the SOA suspension.

 

[BigSur]

i run a 1980 fj40 with no PS and 35's. Its my dd so i drive on the hwy everyday. She moves a little on the road when going 65 -70 mph but i don't mind. get it and drive!!

 

[35inchoverdrive]

I run an F/3spd and 34x9.50's on one of my rigs. It's fine on the road. The 35's will certainly be wider and heavier, but it would probably be tolerable.

 

[fj hunter]

fj40-1/69 with 74 running gear, 35's and feels good

i have only done a few road tests since putting the 35's on my 1/69, with a 74 running gear under the frame, with the 74 f engine too. i spaced them out a bit, and they are 12.5's...they are so much better than the 33-10.5s that i can hardly believe it. i also have the 4 barrel carb by edlebrock (650 cfm) to boost my HP for these large tires, in high 4, the ratio is good to my foot and taste. still have to rock crawl with em to see how that goes, but it will be in low 4 then.

i agree that you opinion of your own vehicle is the key. of course, getting wheels to test drive is the issue.

have fun figuring it out, post up and let us know what your choice turns out to be.

 

[weigellj]

I'll let you guys know how it drives. I am getting the rig tomorrow... Hope to have some bigger meats on it by the end of the weekend.

 

[MtnTrucker]

I have a 74 with SOA suspension and a good running F.5 motor and 4 spd. When I put my 35's on I had the stock 4.10 gears in it. As far as handling at hwy speed it was fine. I had installed all new bushings, TRE's, etc. It did OK (barely) in the flats and really struggled on the slightest of hills. Keep in mind that I am also dealing with 7,000' + elevations that cut the power further, which you shouldnt have to deal with in Wisconsin.

I ended up putting 4.88 gears in it. That gave me much better crawlability off road and lets it perform much better on the highway. It limits my top speed to around 65 which is plenty. My personal opinion is if you are going to stay with stock 4.10 gears then 33's will be the best choice if you drive it a lot on the street. If it's just the occassional street driver and you dont mind a fair amount of time in the slow lane, it can handle the 35's.

 

[badass]

well...

I used to have a 2f with stock carb and ignition with 35 mtrs and aluminum rims, very light combo, 4.88 gearing, and it had trouble pulling 65 on the highway without being almost floored.

then i got 35 tsls with steel rims and converted to tbi, and i only put my fut a quarter of the way on the gas and it pulls 65 This tire and rim combo is MUCH heavier

And just recently i aquired some 39.5 tsl with 4.88 gearing, and a tbi 2f, 3000 rpms, like 73 mph, and once again only a quarter of the way on the throttle.

Btw David i know i've had your engine stand for a while man but i actually just now ordered the advanced adaptor for my truck and won't start on it for another 2 weeks when school is out. But just want to let you know i haven't painted orange yet.

 

[weigellj]

I heard good things about the TBI as well... I'll let you guys know monday what happened... maybe some before and after pics

Actually found a set of 36's on clist.... Might go a wee bit bigger than the 35's I was thinking about...

I don't plan on driving the 40 daily, just occasional runs here and there and then it will be trailered to the trail if its long distance away...

I had a 69 fj40 with a hard top back in the day with 35s, a f and I think it was a 3 or 4 speed on the floor, been so long, I cannot remember.... all I do remember is the thing was so loud it was like riding in a prop plane... Plus it was winter and the heater bairly worked. Those two things kept your mind occupied where you didn't care how fast you were going... Just that you got there and could get out of it.... I don't recall it not being able to hold a decent speed, just that it wasn't a sports car getting there....

God, I am glad I am selling my heep and getting a 40 again..