Is it safe to pin open Transmission thermostat?

You at least want the the WS fluid up in that 180-190 range once your cruising around. Adding a cooler for those hot summers and towing.

 

Definitely has the warming puck. I was looking at a 3rd Gen thread where somebody was seeing 130f around town after pinning and adding a cooler. That’s the situation I DON’T want to be in. I’ll PM you about that thermostat..

 

We be pinned now! Thanks for all the excellent posts in this thread.

 

Also post up on the SC thread about the IPT Transmission. How's the shifting etc...I know John was saying the shifting on 1-2 can vary.

 

Oh for sure! Working through a backlog of mods + tuning then will write it up in the SC thread.

 

Reviving this thread for a second. Anyone running the Improved Racing inline transmission coolers with direct feedback on how these trucks are responding to them? I'll take either unloaded or towing feedback and would like to know if you are using the 20gpm version or the 5gpm.

If I go with the Improved Racing and no the Mishimoto, I'm a bit torn on where to go with it... The 145* option I believe to be simply too cool, the 185* being potentially better than stock based on their stabilization temp values, and then the real contender being the 165*. If these trucks do tend to stabilize at the rated 165*, then I might be more inclined to go with the 185. But if these trucks tend to run closer to the full open temp of 181*, then that's a different story. I think this circles back to the question about transmission pump rates.

Link:
20GPM: https://www.improvedracing.com/high-flow-engine-transmission-oil-cooler-thermostat.html
5GPM: https://www.improvedracing.com/compact-high-flow-engine-transmission-oil-cooler-thermostat.html

Table (appear to be the same):

 

I was looking at the fsc in 145 or 165 degree thermostat. You can always change the thermostat pill up or down. I'm not 100% sure on flow rate. But lines are only -6, 3/8, and not -10, 5/8, so flow rate shouldn't be that high. When I get my new pan I'll try and do a flow rate when I do drain and fill.
With a 180 deg trans thermostat I see up to 190 degree under load, mostly repetitive WOT runs and no towing.

 

I'm trying to remember the timing when I was doing to the full fluid swap via pan fill/cooler line drain. I think we're closer to 5GPM rate than we are 20, but I'd be lying if I said it was scientific in calculation and my example was also at idle.

I believe the OEM thermostat opens at ~183* and is fully open at ~195*, but that could be a few degrees off. Regardless, unloaded, my temps aren't far off from these. Around town is 185'ish, highway is 196'ish. It's interesting thinking through this because it means my truck is running the transmission thermostat fully open just cruising down the highway. Get it, that's the typical use case for these trucks with the warming puck there to help take additional load off the system if being worked harder, but it changes my approach a bit. Towing at highway speeds I'm between 196 and can climb to 210'ish after longer legs. I think I'm calculating myself into a FSM-165 with the 3/8 barbs.

Reviewing the instructions, I see they are rebuildable but I don't see anything about interchangeable pills. Did you get confirmation from them that they are swappable? If so, I won't drop an email inquiring about it. Mishimito advertises that feature which is why they're still on my list, but I think I like this brand (and their apparent understanding of buyer wants for details and installation adapter needs) better. It appears everything I do lately has a 4-8 week lead time so here I am trying to get ahead of the VB and pan upgrades.

 

@bflooks you can pick what thermostat temp you want for fsm and fsc. I believe a greater range than mishimoto.
https://www.improvedracing.com/oil-thermostats/oil-thermostat-rebuild-kits.html

I sold my Toyota oem thermostat. It would be interesting to open it up and see what spring and pill is inside and if it can be modified.

 

My man! Thank you for that link! And only $13.90. That's awesome. Thanks again.

Observation: A slightly different assignment for their temp ranges across these tables

FSM:


FSM Rebuild Kit:
Applications

• FSM-135 High-Flow, Low-Temp Fluid Thermostat
• FSM-145 High-Flow, Low-Temp Fluid Thermostat
• FSM-165 High-Flow Transmission Fluid Thermostat
• FSM-185 High-Flow Engine Oil Cooler Thermostat
• FSM-205 High-Flow Engine Oil Cooler Thermostat
• FSM-215 High-Flow, High Temp Engine Oil Cooler Thermostat

I might have a second OEM thermostat in stock (kept as a safety net that I thought was causing me issues). Once the truck is off to the shop for the motor swap and I can access the inventory side of the garage, I'll see if I can find it. I don't know what I'm looking at/for, so I can either take photos or I can ship it to someone who knows more about the inner workings (hint).

 

Order place last evening, tracking number already provided. Went with the 165 and will be able to provide details this towing season on how it performs without the factory t-stat or warming puck, but with the new VB. I'm going to continue on the WS fluid for this season. It'll be interesting to see the results.

 

Did you go with the 5 or 20 gpm?

 

The "up to" 20GPM. Figured it would give me more options for minimal additional upfront cost.

Without knowing enough about how much pump volume increases with revs, I figured this is best.

 

I agree with that logic. I didn’t know about this thermostat option and it is definitely intriguing.
I have mine pinned and have been watching both the pan temp and converter temp this winter while driving. Even with thr thermostat pinned, I’m seeing 170+ on the converter temp while unloaded on highway.

 

When I removed the warming puck I saw 140-160 in 20 degree temps, no thermostat. According to the WAT videos using the external atf cooler those temps are good. Are the temps in summer in the 190's? It will be interesting to see what @bflooks temps are while under load, towing invthe hills of northern NE. I would think either the 145 or 160 degree thermostat would be great.

 

I assume that is partially the "warming puck" helping heat it up, which is why I'm following the lead of @Mdl and bypassing all of that and just doing the elbows with a dedicated thermostat further away from everything. I'd be happy with 170*, honestly. Not too cool and def not too warm. I'm also hoping that the simplification and divorcing of the systems will yield slightly cooler ECTs, too, especially when under high loads and longer tows. Simplifying the system down at the side of the transmission will also open more space since that's also where my up pipe and turbo collector is located.

@Mdl after seeing the Improved Racing chart for the rebuild kits call out 165* as the "transmission" kit, it sold me on my hunch. For under $15 I'll swap it out if needed. Thanks again for your research and help

 

I got my FSM145 today. Got it on ebay for $100. And 20qts of AISIN 0WS(5.7cst at 212F) to replace the DEX3( 7.1 cst), with shipping/tax was $9.60 qt way cheaper than $13 on Amazon. The DEX3 when cold causes "my" transmission to get confused in 3-4 shifts and a hard shift into 6th. Hopefully the AISIN remedies my issues. Others have used DEX3 and 6 without issues.

 

@bflooks did you receive your improved racing t-stat? Mine was used and didn't get the bracket. Would you be able to give thread pitch and size? I installed it and I forgot to email the company.

 

Acknowledged.

I did receive it Let me better inspect tomorrow AM and I'll get you the additional details.

 

Thanks! It's not heavy but still wanted to have it secured. Appreciate it.

 

They are tiny little guys.

8-32 with 1/4" total thread length.

 

Thanks! The ones I didn't have only 10-24.
Appreciate it. Enjoy the weekend!
Ok. M4 is the bolt that works. Will fab up a bracket but the 145deg t-stat is it. After a few good WOT pulls it was nice and cool. Ambient was 58deg F.