Heater Hose T's - Do NOT Wait!!!

[KMGHMG]

After reading this:

https://forum.ih8mud.com/threads/diy-replacing-heater-hose-pipe-ts-important.610334/

I decided to change my heater hose T's today. I figured it wasn't completely necessary yet since I have a relatively low mileage 99 LX (125k on the clock). But it was a rainy day here in San Antonio (for a change) and I had nothing else going on after bleeding the AHC system and replacing the cabin air filters (they were NASTY). I bought OEM T's from the local Lexus dealer.

Long story short, it's a very good thing I changed them. The hot side T was so brittle that it simply fell apart when I tried to loosen the first clamp. Here's a pic of the two old T's.

There was MAYBE a sign that the hot side was weak. I say maybe because there was a very slight bit of dried coolant where the hoses met the T. That's it. And I really had to look hard and use a bright flashlight to see it. Otherwise, it looked and felt ok until I tried to loosen the clamp. By hand, it felt fine.

So, I did some reading again in that thread I posted above so I could see if there's a pattern to this failure in terms of years and mileage.

Some members found NO problems with theirs when they changed them, per the thread above. The following found their T's to be ok:

1999 with 180k
1999 with 125k
1998 with 112k
2000 with 153k
2003 with 120k

However, other members had bad T's:

1999 with 135k
2003 with 123k
And of course my 1999 with 125k.

Long story short, if you're reading this and you have a 100 series with, say, 90k or more on the clock, change the heater hose T's asap. Do not wait. Some models of the same age and mileage will be ok, and others will not be.

Matt

 

[sdnative]

Always good to keep on top of the cooling system, including the Tees. Mine were brittle and starting to fall apart (not as bad as yours though) at 115k.

 

[TXLX100]

Yikes. Slap in a new thermostat while you are at it. The two big things that will stop a 100.

 

[KMGHMG]

Yikes. Slap in a new thermostat while you are at it. The two big things that will stop a 100.

Good point. I replaced the thermostat a few weeks ago.

 

[GregLCA]

Does anyone know what the ID of those t-fittings are? (I'm assuming it's metric, not SAE?)

There are plenty of places to buy a quality stainless replacement (Summit, JEGS, etc). If this failure is truly as catastrophic as everyone here is implying, it would be smart money to just swap them with a high-quality part that will never corrode or disintegrate...

I could post up some candidates of someone provides dimensions.


-G

 

[TXLX100]

Does anyone know what the ID of those t-fittings are? (I'm assuming it's metric, not SAE?)

There are plenty of places to buy a quality stainless replacement (Summit, JEGS, etc). If this failure is truly as catastrophic as everyone here is implying, it would be smart money to just swap them with a high-quality part that will never corrode or disintegrate...

I could post up some candidates of someone provides dimensions.


-G

There are some prior posts regarding this. If I recall, @jonharis replaced with brass.

 

[Toyo72]

It does look like a great candidate for an aluminum or stainless steel upgrade part and be done with it.

Do the -06-07 models have the same T-fitting? nevermind - yes they do, saw that in the other thread referenced. Was hoping that maybe Toyota upgraded at some point from plastic.

 

[TXLX100]

See post #36, might be a good resource for some brass T's

https://forum.ih8mud.com/threads/di...-pipe-ts-important.610334/page-2#post-7940866

 

[2003lx470]

Recently purchased the 2 T's and thinking why not replace during the Timing Belt change. I still have 20k miles to reach 90K (2003 LX 470). After reading your experience, very much concerned the conditions of the T's.

Side note: This June, moving from Houston to San Antonio.

 

[kz195688]

Some of us, including myself, have used brass fittings to replace the plastic "T"s. I purchased them off Amazon. The Amazon info was provided by another mud member concerning the T issues. I believe the T replacement article is in the FAQ section on this site. Some use the Toyota T because they have lasted at least 100k. To each his own. Remember to change the hoses and maybe clamps at the same time. Good luck.

 

[TXLX100]

I used plastic ones. My plan is to add heater T's and thermostat to my 90k's. Good time to do it since coolant is typically drained during the service.

 

[re_guderian]

... The two big things that will stop a 100.

and an ignition cylinder, and a transmission, and a brake master cylinder, and a front differential, and a timing belt, and a throttle position sensor, and... , but yeah, tees are probably the cheapest and easiest of all things that can stop a 100.

 

[KMGHMG]

I thought seriously about getting the brass ones, but I was already at the dealer and thought that 100k miles on the new plastic ones would last me at least a decade. Having said that, I think metal ones of some kind are definitely a better option.

 

[TheForger]

Are these stainless T's easy to find? As in, would I be able to go down to my local ACE or Fuller & Son and be able to pick them up? If it is that easy I might be looking into replacing the plastic OEM ones I replaced July.

 

[GregLCA]

Are these stainless T's easy to find? As in, would I be able to go down to my local ACE or Fuller & Son and be able to pick them up? If it is that easy I might be looking into replacing the plastic OEM ones I replaced July.

Not quite THAT easy to find I suspect, but everything exists on the Interwebz.

I know of a couple specialty stainless fastener companies, that might carry a "T" for this... But I don't know the dimensions. (Specifically the I.D.) to look for a match.

I'm the kind of guy who would rather just spend the money on an upgraded part and never have to worry about a failure (on THAT particular part anyway!) ever again....


-G

 

[Kigiin]

and an ignition cylinder, and a transmission, and a brake master cylinder, and a front differential, and a timing belt, and a throttle position sensor, and... , but yeah, tees are probably the cheapest and easiest of all things that can stop a 100.

And starter.

My brass Ts are still going strong.

 

[TheForger]

Not quite THAT easy to find I suspect, but everything exists on the Interwebz.

I know of a couple specialty stainless fastener companies, that might carry a "T" for this... But I don't know the dimensions. (Specifically the I.D.) to look for a match.

I'm the kind of guy who would rather just spend the money on an upgraded part and never have to worry about a failure (on THAT particular part anyway!) ever again....


-G

Oh I am the exact same way - I would much rather replace a part with something that I know will never fail again in the lifetime of the vehicle. If/when you get those I.D. dimensions and find a stainless replacement for the heater T's I would be interested in getting myself a pair as well.

 

[hankinid]

I just measured some old heater hose T's with my ultra-precision Harbor Freight $10 digital calipers...

T's measure 0.66" on the run, and 0.55" on the T...measured past the barb.

I don't have spec's handy on Japanese hose sizes...and as much as I love this place, I'm not going to disassemble one of the assemblies on the truck.

If cost is not an issue, stainless would be beautiful...check https://forum.ih8mud.com/threads/jtr-hose-splicers-w-w-o-steam-port-heater-hose-ts.541170/

If you're not feeling spendy, brass ought to work perfectly.

What really helped me during T replacement were long angled Harbor Freight pliers...<$20 or so out the door... http://www.harborfreight.com/2-pc-20-offset-45-angle-long-reach-pliers-61587.html

...those 2 and the 2 next to it. Search "long pliers" from the home page.

hth

Steve

 

[HFDPNL]

Wow, no joke on the "don't wait."

Replaced mine today, I ordered them a while back and wasn't too concerned with it. I figured I would replace them today, while I had some time, and before I go on a multi-state trip. Pulled the passenger side without much drama, and I was beginning to think perhaps they had been serviced before.
Then, I pulled the driver's side and noticed one side of the T looked like it was chewed down and my first thought was that some joker had cut down the end to make it easier to install. When i looked in the tube I found the rest of it and removed it....Really surprised me.

 

[PADDO]

Do you have to drain the coolant in order to replace the T-fittings, or can you pull them with minimal coolant loss?

No drain necessary, you loose maybe a cup of fluid.