Complete Coolant Hose Replacement (3.4L V6 5VZ-FE)

[mtbtim]

Hey Dudes,

Since your rig with the 3.4L V6 5VZ-FE Engine has been around for 20+ years, you've probably logged a whole bunch of miles on it. One maintenance item that quite a few people forget is all those heater hoses at the back of the engine, the coolant bypass hoses under the throttle body and the oil cooler hoses along the driver side of the engine block.

This video came about because my buddy Aaron blew a heater hose on a 4wheeling trip in the California Sierra Nevada Mountains. We were able to cut out a short section that burst and we're luckily able to get him off the trail and home.

So, if you have a ton of miles on your engine, which I think most do at this point, this is a maintenance job you probably want to consider so you're not left stranded somewhere.

I hope you Dudes like the video. Happy Wrenching!
Timmy the Toolman

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[T4R2014]

Great video. This is a necessary job on every 3rd gen considering they are all over 22 years old now.

 

[thegipper]

Another excellent video Tim. I had a leak on one of those hoses at the rear of the engine and was able to replace it without removing the upper/lower plenum but it was a nightmare. If I ever had to do it again, I would remove the plenums.

 

[mtbtim]

Another excellent video Tim. I had a leak on one of those hoses at the rear of the engine and was able to replace it without removing the upper/lower plenum but it was a nightmare. If I ever had to do it again, I would remove the plenums.

Yeah, when a hose blew on my buddy Aarons 3rd Gen while we were 4wheeling in the Sierras, and I saw where the leak was, I immediately knew I would get the plenums out of the way to have an easier time accessing the hose. The hose that blew was one of the heater hoses that attaches to the bypass pipe that run under the intake manifold. I couldn't imagine trying to access that bottom constant tension clamp without getting the plenums out of the way.

Some guy commented on YouTube and said he did all the hose replacements without removing the throttle body or plenums. That must have involved a whole lot of patience and/or cursing. The job is hard enough with the plenums and throttle body out of the way. Those cotter pin hose clamps are seriously annoying. Whoever the Toyota engineer that came up with that design did auto mechanics a disservice.

 

[2TH4IST]

I can't quite remember the exact time, but a few years ago I did all my coolant hoses with OEM. Surprisingly it wasn't that expensive, somewhere in the 250ish range. Since the oem ones lasted 24 years, I went with oem again. Did the oil cooler seals too. Also did a distilled water coolant flush.

 

[blarchitect]

Just did all them about 2 weeks ago without removing throttle or intake lol

 

[NachesPass4x4]

I'm working on a neglected 2000 SR5, that I picked up. The hard lines going to the center console rear heater are rotten, bad enough I don't know how they still hold fluid. I don't know if its in the video or not but it looks like a problem area worth inspecting when working on the cooling system.

 

[3bears]

nice video glad you covered the intake tubes b4 something fell in,
thanks also for listing the tools, THis spring I need to do vc gaskets, so will be doing all the hoses too. Interesting however, I knew the oil cooler hoses and gaskets would be a hassle, and trying to be pre issue, actually took it to a yota shop ( independent) and asked them to do, they had it for a day, called me up and said did not need so did not do. I said I wanted it done b4 an issue, they said not needed..gave me car back no charge, but had to pay for hoses and gaskets, which they gave me....for future. I think they just did not want to do it. going to do as many vacum hoses as I can. Radiator etc all done 2 years ago when I did timing belt

otherwise, really appreciate all the videos

 

[HiLife]

Always appreciate your effort in making these vids and posting in this forum!
Keep them coming.
I know I need to do this coolant hose refresh too.

Also, need to do all 5 outside window rubber seals while they're still available. Things will get frustrating when those break, and flexible replacements are hard/impossible to find on my 24yo.

 

[2TH4IST]

. I said I wanted it done b4 an issue, they said not needed.

It's a real PITA that seal is. And I had a 1 inch body lift. Gasket cinch or Indian head shellac works wonders holding the o ring in place. Leave the hoses off makes it easier.

 

[JohnMc]

I'm working on a neglected 2000 SR5, that I picked up. The hard lines going to the center console rear heater are rotten, bad enough I don't know how they still hold fluid. I don't know if its in the video or not but it looks like a problem area worth inspecting when working on the cooling system.

If you have pick-and-pull junkyards in your area, see if any of them have a 2001-2002 model year 4Runner. They'll have the stainless (or aluminum? can't recall) hard lines for the rear heater. 1996 - 2000 have the painted steel lines that will rot out.

I did that a long while ago on mine. Paid $10 for the lines from the junkyard, replaced all the rubber lines while I was at it. I was amazed the old steel lines hadn't started leaking yet, bubbles of rust under the paint, flakes coming off, I bent one slightly taking it off and it cracked in a thin spot.

 

[NachesPass4x4]

If you have pick-and-pull junkyards in your area, see if any of them have a 2001-2002 model year 4Runner. They'll have the stainless (or aluminum? can't recall) hard lines for the rear heater. 1996 - 2000 have the painted steel lines that will rot out.

I did that a long while ago on mine. Paid $10 for the lines from the junkyard, replaced all the rubber lines while I was at it. I was amazed the old steel lines hadn't started leaking yet, bubbles of rust under the paint, flakes coming off, I bent one slightly taking it off and it cracked in a thin spot.

Thanks for the info, I was unaware of this.

 

[mtbtim]

Just did all them about 2 weeks ago without removing throttle or intake lol

I have to imagine that required more swearing than I did doing this job. You just have way more access with the plenums and throttle body out of the way.

 

[mtbtim]

nice video glad you covered the intake tubes b4 something fell in,
thanks also for listing the tools, THis spring I need to do vc gaskets, so will be doing all the hoses too. Interesting however, I knew the oil cooler hoses and gaskets would be a hassle, and trying to be pre issue, actually took it to a yota shop ( independent) and asked them to do, they had it for a day, called me up and said did not need so did not do. I said I wanted it done b4 an issue, they said not needed..gave me car back no charge, but had to pay for hoses and gaskets, which they gave me....for future. I think they just did not want to do it. going to do as many vacum hoses as I can. Radiator etc all done 2 years ago when I did timing belt

otherwise, really appreciate all the videos

The shop took one look at it, realized it would be a pain in the ass and saved face by telling you the hoses were fine. I doubt they even reached their hands in there and touched the hoses. What shop passes on a job the customer wants done? There are shops with integrity and don't replace parts that are fine, but I agree with you, they didn't want to do it because the access is less than optimal. Nobody can argue replacing coolant hoses that are 20+ years old is wasteful spending.

 

[blarchitect]

I have to imagine that required more swearing than I did doing this job.

Yes, the air was blue with all the cuss words, but my selection of pick tools and pliers saved the day.

 

[mtbtim]

Yes, the air was blue with all the cuss words, but my selection of pick tools and pliers saved the day.

I guess since I've taken the throttle body and plenums off so many times, I made quick work of it.

The oil cooler hoses and resealing the oil cooler to the block was the biggest pain in the butt. I'm going to put out a separate video for that job, which will be the same footage from the complete coolant hose video. I decided it should be its own separate video, because so many people have asked for help with replacing those hoses or asking how to fix an oil leak from the cooler.

 

[SuddenStorm]

Now I wish I had replaced all these when I already had it apart when I did the valve cover gaskets a few months ago. Adding it to the list of "Things I want to do in the hopes of never being stranded"

 

[JohnMc]

I let a few semi-related tasks build up and did them in on coordinated effort. Replaced the original steering rack (with a new OEM rack, rebuilt racks never last very long in my experience), the oil cooler hoses and seals, the power steering pressure and return lines (pressure line was starting to look a tiny bit 'damp'). Reaplced the front diff (with an Eaton e-locker diff in 4.88 gearing from East Coast Gear), and resealed the oil pan.

Much better access to get to some things with other things our of the way. I have a 1" body lift which makes access to the side of the motor through the front hweel wells a little better, but it's still a miserable job getting to those oil cooler hoses.