3800 Swap: 5 Speed to 4T65HD (Page 1/1)
Stricken SEP 26, 01:15 AM
If you've seen my other postings, you'll know that I have been fighting issue after disturbing issue on my 88 Formula to do a 3800 swap (thanks to those who have been providing input thus far). The most recent shock was a large piece cut out of the bellhousing on my Getrag. I decided to just ditch this trans as the rest of the car has proven to be a one problem wrapped in another, and I expect the inside of the trans to be no different. I considered an F23, but I have the 4T65HD already, so I'm just going to run with that.

Besides mounts and axles, what all will I need to run the 4T65HD? I've ordered an auto shifter and cable already, and I'm having the harness built for me.
Dennis LaGrua SEP 26, 09:07 AM
Here are the extra steps.. I did a manual to auto 4T60e conversion and it wasn't difficult but it did involve many steps. The 4T65eHD requires the same steps. From memory:
1. Remove manual shifter (4 bolts) . Install shifter and cable. Be prepared to first remove the console and the support structure, jump start safety switch wires. It will now be on the selector switch on the auto transmission
2. Modify and reverse install the trans shift selector arm, fabricate new shifter cable bracket that goes on the transmission.
3. Remove clutch pedal and attached support bracket. You will need to cut the clutch arm bolt with a wheel. Join both ends of the pedal start switch wires. That will now also be on the trans selector switch. The clutch pedal bracket is just an add on item. The brake pedal bracket will be retained.
4. Remove the small manual Brake pedal and replace it with the larger auto brake pedal using the bushings, spring and shorter bolt. The same brake pedal bracket is used on auto and manual cars. Do not attempt to replace this bracket. It is a nightmare job and not necessary.
That's it and get ready for some soreness the next day from twisting to work under the dash. The pedal part is really a job for a contortionist but easy if you remove the seat.

------------------
" THE BLACK PARALYZER" -87GT 3800SC Series III engine, custom ZZP /Frozen Boost Intercooler setup, 3.4" Pulley, Northstar TB, LS1 MAF, 3" Spintech/Hedman Exhaust, P-log Manifold, Autolite 104's, MSD wires, Custom CAI, 4T65eHD w. custom axles, Champion Radiator, S10 Brake Booster, HP Tuners VCM Suite.
"THE COLUSSUS"
87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H
" ON THE LOOSE WITHOUT THE JUICE "

[This message has been edited by Dennis LaGrua (edited 09-26-2020).]

darbysan SEP 26, 10:56 AM
Also consider the Trans cooler. You will either need to plumb lines to the radiator ( may or may not have the cooler built in), or add a cooler, or both.

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'87 GT , '00 3800 Series II SC, 4t65e, Vue Power Steering. (SOLD)

Stricken SEP 26, 01:03 PM

quote
Originally posted by Dennis LaGrua:

Here are the extra steps.. I did a manual to auto 4T60e conversion and it wasn't difficult but it did involve many steps. The 4T65eHD requires the same steps. From memory:
1. Remove manual shifter (4 bolts) . Install shifter and cable. Be prepared to first remove the console and the support structure, jump start safety switch wires. It will now be on the selector switch on the auto transmission
2. Modify and reverse install the trans shift selector arm, fabricate new shifter cable bracket that goes on the transmission.
3. Remove clutch pedal and attached support bracket. You will need to cut the clutch arm bolt with a wheel. Join both ends of the pedal start switch wires. That will now also be on the trans selector switch. The clutch pedal bracket is just an add on item. The brake pedal bracket will be retained.
4. Remove the small manual Brake pedal and replace it with the larger auto brake pedal using the bushings, spring and shorter bolt. The same brake pedal bracket is used on auto and manual cars. Do not attempt to replace this bracket. It is a nightmare job and not necessary.
That's it and get ready for some soreness the next day from twisting to work under the dash. The pedal part is really a job for a contortionist but easy if you remove the seat.



Excellent! That doesn't sound bad at all.
Stricken SEP 26, 01:04 PM

quote
Originally posted by darbysan:

Also consider the Trans cooler. You will either need to plumb lines to the radiator ( may or may not have the cooler built in), or add a cooler, or both.




Yep. The radiator has the cooler built in. I'm debating which is the easiest route.
Dennis LaGrua SEP 27, 02:46 PM

quote
Originally posted by Stricken:


Yep. The radiator has the cooler built in. I'm debating which is the easiest route.



Oops forgot about mentioning that. With the 4T65eHD I would use the Champion radiator that has a larger transmission cooler. The stock Fiero A/T radiator with the cooler may work but you do not want your trans oil temperatures over 190*. You may also try adding an air cooled transmission cooler but I've found that they do not work as well. I purchased a roll of 3/8" aluminum tubing from Summit Racing equipment $18 for 25' roll. Ran the cooler lines underneath using stainless steel/rubber lined hose clamps.

------------------
" THE BLACK PARALYZER" -87GT 3800SC Series III engine, custom ZZP /Frozen Boost Intercooler setup, 3.4" Pulley, Northstar TB, LS1 MAF, 3" Spintech/Hedman Exhaust, P-log Manifold, Autolite 104's, MSD wires, Custom CAI, 4T65eHD w. custom axles, Champion Radiator, S10 Brake Booster, HP Tuners VCM Suite.
"THE COLUSSUS"
87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H
" ON THE LOOSE WITHOUT THE JUICE "

Stricken SEP 27, 09:25 PM

quote
Originally posted by Dennis LaGrua:


Oops forgot about mentioning that. With the 4T65eHD I would use the Champion radiator that has a larger transmission cooler. The stock Fiero A/T radiator with the cooler may work but you do not want your trans oil temperatures over 190*. You may also try adding an air cooled transmission cooler but I've found that they do not work as well. I purchased a roll of 3/8" aluminum tubing from Summit Racing equipment $18 for 25' roll. Ran the cooler lines underneath using stainless steel/rubber lined hose clamps.




I heard a rumor that ZZP says a cooler isn't needed on the 4T65, but I'm pretty suspicious of that claim. Heat is what kills transmissions, so I don't see the sense in not having a cooler.
Dennis LaGrua SEP 28, 11:11 AM

quote
Originally posted by Stricken:


I heard a rumor that ZZP says a cooler isn't needed on the 4T65, but I'm pretty suspicious of that claim. Heat is what kills transmissions, so I don't see the sense in not having a cooler.


Above about 190*F, the transmission oil oxidation rate doubles with each 20° degrees F increase in oil temperature. I cannot see running without an oil cooler being beneficial. What I can believe is that you can run without ADDING an extra oil cooler to the one already in the radiator.


------------------
" THE BLACK PARALYZER" -87GT 3800SC Series III engine, custom ZZP /Frozen Boost Intercooler setup, 3.4" Pulley, Northstar TB, LS1 MAF, 3" Spintech/Hedman Exhaust, P-log Manifold, Autolite 104's, MSD wires, Custom CAI, 4T65eHD w. custom axles, Champion Radiator, S10 Brake Booster, HP Tuners VCM Suite.
"THE COLUSSUS"
87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H
" ON THE LOOSE WITHOUT THE JUICE "

[This message has been edited by Dennis LaGrua (edited 09-28-2020).]