Potential 1991 Fj80 purchase. Lots of questions (1 Viewer)

[tooofast2002]

Hi, i am seriously eyeing a 1991 FJ80 to build out as mild overlanded. It has the 4l six in it and i see there are some great v8 swaps that have been done but that's just me dreaming. My real question is around the 4wd set up. Its an Auto with full time 4x4 and has a diff lock. I wanted to check I could add an ARB locker to it down the road. I assume yes but you guy's know all the little bits that would trip me up. Other than rust what else should i be looking for? there was a killer write up for buying my FJ40, is there something like that for the 89s?
Thanks as always in advance for the help

Cheers
Dave

 

[Fj80oregon]

You can search every answers to all your questions you have. This is a awesome forum but the knowledge that is already available is easily found. Look at Slee Offroad newbie guide.

 

[DesertCruiser80]

I wanted to check I could add an ARB locker to it down the road.

Yes, you can add an ARB air locker, both front and rear. You cannot add an e-locker (like Eaton Harrop) on the rear of a '91 or '92. Only the full float rear axles on the '93-'97 accept those. I did a rear axle swap to a later model axle for that reason.

 

[tooofast2002]

Thanks, am i going to regret the 4lL engine and is it a real dog on 35s? I plan to regear when i do the lockers, but thats some time off. and what is the stock gearing?

Thanks
Dave

 

[cobrasteen]

This forum and YouTube are your friends in this case. I just bought an 80 last week and took about a week of constant research to figure out the main points to look for. OTRAMM has a really good starting point for pre-inspection and as others have mentioned, the FAQ has a lot of good info.

80 Series Prepurchase Inspection Pointers

Also ask in advance if there are any issues, CEL, any other lights, gauges not working, etc. And then search those up on the forum or other places so that when you go there you can do a bit of troubleshooting before deciding on purchasing. (This means bring a set of tools, gloves, lights, notebook to write on, etc)

Check if the differential works. If you dont know how to check it - YouTube. Only the front diff worked on the one I bought, but I troubleshot with the PO right there in his driveway and got the CD and RD to work after popping some sensors off and cleaning them.

Check for anything that looks non OEM and ask about it! Mounting holes, RTV, glues, cables, etc.

Try to get as much service history as you can from the PO! Dates, parts replaced, original parts if they still have them, etc.

Good luck!

 

[YMT]

80-series FAQ for General Info, Modification and Repairs

The Frequently Asked Questions (FAQ) for the 80/LX450 series tech section continues to be a work in progress. The goal is to have links in the below to other threads and tech articles. By having these linked, instead of pasting the text, the threads will remain live. The live threads can...

forum.ih8mud.com

These are 30 year old vehicles, so many chances for shade tree mechanic work, aftermarket add ons, and lack of maintenance, in it's past. Keep that in mind when checking the vehicle out. It may be worthwhile to take it to a reputable shop for inspection pre-purchase, or take a friend with who knows the 80 series. Or, post up in your local 'Mud clubhouse, and see if anyone would be willing to check out the vehicle with you.
That said, plan on baselining the vehicle, if you do buy it. Plenty of threads on the topic. Plan on about $3k in baselining costs; more or less, depending on if you do the work, or a shop.
Also, FJ/FZJs are finicky about parts. They like OEM, and sh!t out non-OEM parts. Plenty of threads on this too.
There's a wealth of knowledge on here. Search is your friend. You should find virtually everything on here, unless you pioneer something in your build.

Good luck

 

[White Stripe]

Get a 93 or newer. Don't get a 91. They are dogs.

 

[ajax1]

I would look at 95 and up with obd2.
91 92 do not have full float rear axle( can swap in)
91 92 have smaller front brake set up(can swap)
Some 93 to 94 have the semi float rear axle
Early 93s have I believe ,was the efi relay wiring issues
Some early 95s have obd1.
Are you gonna engine swap?
3fe is a solid engine but slow
1fzfe is solid engine and little faster
I prefer the 1fzfe
93 and up have a viscous coupler in the tcase
95 and up have different birf size in front axle
Buy the cleanest best one you can find

 

[Marco Lau]

Thanks, am i going to regret the 4lL engine and is it a real dog on 35s? I plan to regear when i do the lockers, but thats some time off. and what is the stock gearing?

Thanks
Dave

I am on 37s, full armor, beadlocks ,regear to 4.88 and it is doing just fine. Be thankful you dont have to worry about HG and engine rebuild...
I prefer my 3fe over 1fzfe...

 

[tooofast2002]

Thats a mountain of good info. one question i cannot seem to grasp is the center diff lock,. where there versions of the 80 that were 4wd full time but did NOT have the center diff lock? Sorry i am not used to 4wd drive stuff. vs my usual 4x4 4x2 vehicle where you engage the T-case and it engages both prop shafts equally.

If there are 4wd 80s out there that DONT have a center diff lock that is going to reduce off road performance even with front and rear ARBs added as the power would just go to the front or rear if its slipping.... right?

thanks
Dave

 

[Marco Lau]

They all have Center diff locks....(CDL) the 3FE has a factory installed CDL on dash for user to engage during 4H...while the 1fz-fe or the 4.5L has the harness ready, but not installed on dash. You can engage CDL via 4Lo

 

[leonard_nemoy]

91-93 are really really gutless
93-97 are really gutless

All 80 series are gutless by today's standards. Especially if you live in a mountainous region and do a lot of elevation gain.

My 91 with 280,000 miles did get better gas mileage than my 97 with 120,000 miles on the clock.


After owning both I would say get a 93 or newer. Not because of the power difference but because of parts availability. The 3fe has less new parts available and it would be a harder motor to get rebuilt correctly.

Oh yeah, and none of this is true of you live in Cali. In Cali they will both get 18+mpg, clear 37's with a two inch lift, and have enough power to tow a 30' boat......

 

[Marco Lau]

No way around it....get one that best fits your usage.
the alternative to get a Jeep..Jk or JL, toss on 37s and armors, and your still looking at a gutless engine that will overheat and upgraded 1 ton axles and a future V8 swap. Ask me how i know...lol
cheers.

 

[tooofast2002]

Done the jeep thing (stretched 99tj and 08 over built Rubicon on 37s) , now I'm growing up I've moved on to Toyota. Your 100% right they are ALL gutless compared to modem vehicles and why RIPP makes so much money from their Jeep super chargers. For me its going to be a value proposition and the enjoyment of the build. I push paper in a high stress job all day so getting under a vehicle and shaping it to my vision is one of my greatest joys. My wife always says loose interest as soon as I finish the build and I am blessed i now have a place i can really take my time and want to do something where i am not rushed or have space issues. This thread has been just great for me, huge amounts of info and really helped me think of what want the 80 for and what its use is going to be. The jeeps were all for the rocks 1,000 of pound of 1/4 inch armor and 4:1 T cases. At some point you end up with a tank on 4 wheels, they just get so heavy. I may go that route with the FJ40 that got me infected with the Toyota bug, but i think the 80 is going to be a different build. Again fantastic advice, i appreciate it all and will have to take some time to digest it all.

One question that has surfaces i have seen some mods about charging the gear ratio in the t-cases. is this done commonly ? i did love that super low gear I had in the Atlas transfer case.

Thanks, really appreciate the posts and advice. what a great forum!

Dave

 

[DesertCruiser80]

The 3fe has less new parts available and it would be a harder motor to get rebuilt correctly.

Not to hijack the thread, but why would the 3FE be harder to rebuild? Seems like a engine design as ancient and simple as the 3FE would be simpler to rebuild no? I do agree with parts availability though.

 

[Broski]

91-93 are really really gutless
93-97 are really gutless



Oh yeah, and none of this is true of you live in Cali. In Cali they will both get 18+mpg, clear 37's with a two inch lift, and have enough power to tow a 30' boat......

Can you please tell me your secret, mine can do none of these superhero feats

 

[leonard_nemoy]

Not to hijack the thread, but why would the 3FE be harder to rebuild? Seems like a engine design as ancient and simple as the 3FE would be simpler to rebuild no? I do agree with parts availability though.

Maybe not harder to rebuild per say, just harder to "get" rebuilt by a reputable shop. Less guys out there familiar with rebuilding the 3fe compared to the 1fz-fe. Plus the parts availability issues would also seemingly make it harder to get rebuilt.

Can you please tell me your secret, mine can do none of these superhero feats

The comment was meant to be sarcastic trollbait and is based on many comments I have seen posted on this forum by commifornians over the years.

 

[DesertCruiser80]

Ahh, makes a bit more sense. Could be that more people know how to rebuild the 1fz-fe because there's more of them (and head gasket go boom )

 

[Broski]

Maybe not harder to rebuild per say, just harder to "get" rebuilt by a reputable shop. Less guys out there familiar with rebuilding the 3fe compared to the 1fz-fe. Plus the parts availability issues would also seemingly make it harder to get rebuilt.


The comment was meant to be sarcastic trollbait and is based on many comments I have seen posted on this forum by commifornians over the years.

I was being sarcastic as well.

 

[Devils Paw 80]

Thanks, am i going to regret the 4lL engine and is it a real dog on 35s? I plan to regear when i do the lockers, but thats some time off. and what is the stock gearing?

Thanks
Dave

It is a real dog on stock sized tires. Gearing is 4.11.