Heat from manual transmission

[Vegas4Runner]

'93 V6 5spd.
I have only had this rig a few months but I have noticed a lot of heat coming into the cab from the transmission hump. So much so that the shift boot and surrounding plastic are almost unbearable to the touch, and that is at highway speeds when the transmission should be getting the most airflow. The transmission works great with clean shifts and no slipping. I replaced the fluid just after I bought the vehicle but the heat issue has been there since day 1.
Are the 2nd gen's just really poorly insulated or should I be concerned?

 

[T?@\7]

That's not right mate, sorry idk how to help, but that's now how its supposed to run. Goodluck

 

[Vegas4Runner]

The funny thing is that I get about 20mpg highway so I have a hard time thinking that there is something seriously wrong in there. I haven't tried switching to synthetic and that may be my next move, but before I make the switch I wanted to hear from others on their experiences.
Also, are there additional things that I can do to block the heat from entering the cab?
Would something like Herculiner applied either inside the cab or under the bucket do any good?

 

[T?@\7]

Would something like Herculiner applied either inside the cab or under the bucket do any good?

Yes, when I'm driving long dist at high-speed/load/rpm I notice my sticks, both tranny and x-case do heat up.... I'm planning on doing a full interior dynamatting to keep sound and extexterior temps from reaching the passenger zone. I might do herculine and then something like dynamat....

 

[T?@\7]

What rpms is she running at?

 

[Vegas4Runner]

At highway speeds the RPM's hover just above 3k, usually no higher than 3,250.

 

[KidVermicious]

Has the rig been recarpeted? I get a lot of heat off my tunnel because a PO recarpeted the interior and didn't put anything between the carpet and the body to block the heat.

 

[Vegas4Runner]

Has the rig been recarpeted? I get a lot of heat off my tunnel because a PO recarpeted the interior and didn't put anything between the carpet and the body to block the heat.

Good question. I am pretty sure that the carpet is original, but that does raise the question as to whether that would be a way to increase the insulation by adding something under the existing carpet.

I am more concerned with whether the heat is an indicator of something wrong.

 

[csrobb007]

I had heat issues (or what I thought might be) and in knowing that I was going to re-paint the truck, decided to add a scoop to direct air behind the engine and down the tunnel...it worked, with the heat on the inside being barely noticeable now.

 

[the_dingman]

It's probably not the transmission, but the catalytic converter that is right next to it. The cat throws a LOT of heat, especially if the heat shield is missing, or it's starting to clog.

 

[Vegas4Runner]

As far as the scoop goues, is there such thing as a scooped hood that swaps in, or would I need to buy one of the autozone cut-a-hole-and-attach-it-on scoop kits that guys put on their civics?

As for the cat getting clogged up, is there any additive that cleans the cat. I know Lucas oil and seafoam fanatics will tell you the stuff cures cancer (I've used them both in this rig a few times so don't anybody go getting offended), but is there anything that really works on clearing out some of what builds up in there?

 

[the_dingman]

Seafoam will do more for the cat than Lucas will, but neither will cure a really bad cat. They will fix a lot of other issues though.

 

[csrobb007]

I looked at different ways to get cool air under the hood...to do the scoop like the new Celica's...the support structure of the hood needs to be changed to the point of running out of room between the hood and manifold...no good without support, so I did the external type, molded it to the hood (versus stick on like the Honda guys you mentioned) and painted with the rest of the triuck...Fiberglass hood is an option at about 300 and up. Don't know about the cat / heat thing...mines gone, and I've got two coolers, one in the radiator (stock), and from there to an aftermarket one behind the grills in the bumper. No heat problem.

 

[Vegas4Runner]

Thanks for all of the input guys. It looks like I have a few things to try out. First off, the scoop on the hood sounds like a must but will probably have to wait until spring. In the meantime I will seafoam her again (the neighbors hate it when I bring on the cloud) and I will probably switch to synthetic next time I change the gear oil just because it us a good idea. I'll let you know next spring when it warms up how well it all worked.