Gibbles

Hemi,
sorry i could have been a little less blunt with my reply.
I'm just sick of people telling others to not change their transmission fluid.
That's like saying you should not change your motor oil because you ran it over x miles.

transmission fluid is lubricant, you have bearings, bushings and metal on metal contact that is designed to have oil flow between them.

Part of the design uses a wet clutch system that allows them to slip a little with out burning up.

I think the majority of people think an auto transmission works by some magic spell and transmission fluid contains magic sparkles or pixie dust.

ghoastrider1

On cost. I pulled my own tranny in the back yard, then took it to the shop. Cost me 1500 bucks ( if I remember right) with a new converter. Tranny work aint cheap. Best of luck with yours. Also,many shops "swap" trannys with a rebuilder outfit. Yours is stamped with your vin number. may not matter but I told the shop don't swap it, rebuild it cause of the numbers.

hemivett

No worries. We all have our days.

I did say if the fluid hasn't been changed every 30k. I'm an avid believer in it. It's the people who roll in with 140ķ on their fluid, is what I'm talking about. For some reason now they decide to be proactive with their maintenance, and speed up the inevitable. I actually built the tranny's in the 3 cars I have now, and I know dirt is the enemy. I had the one in my blazer built twice, and neither shop did the valve body upgrade to my l60e, so they would last a couple years, and I would be back where I started from. So I just decided to learn how, and do it myself. First one was very intimidating, but they got easier with time. Now I kinda enjoy it! Peace. h

ucfsaxman

Thank you! I thought that price was awfully high and I was thinking for that kind of money I could damn near have a race transmission built or at least strengthen the transmission for more heavy duty usage. I'm definitely going to check out this other shop I really only went to the first one because it was the weekend and closer to where I lived but I trust this other shop that I have been to before to do better work and charge a more reasonable fair price. I'll see what they say and then go from there as far as rebuilding or buying another unit entirely. Does anybody have any recommendations for small upgrades to do on the transmission while it is apart and out of the car?

Gibbles

I'm not quite up on what weaknesses a 91trans has but my 84 i replaced everything but the input drum. However i upgraded my engine hp by quite a bit, and the early transmissions had some issues.

I would suggest upgrading the pistons in the input drum to the later bonded pistons. You will also need the later spring cages to make it work. It's a cheap upgrade.

Also in my 84 the low reverse piston is weak, later part is a drop in part.

I also picked up a 5 pinion planetary gearset with the carriers, i believe they came out of a low mileage 4l65e from a trail blazer.

Much improved oiling and its much quieter than the 4pinion set.

There is also this input drum reinforcement kit made by sonnax, fixes a big weak spot and it's less than $80 if i recall.

Rest of the upgrades depend on what you would want to change about how it shifts, pr how it launches.

A higher stall torque converter would make your car launch off the line faster, and it also makes it easier to get the tires to break loose.
Just think about where the car really started to build power and target the stall in that range.

Gibbles

Also i bought a video on how to rebuild a 700r4 off of ebay, seller was thirdgen or something close.
It helped a ton, but for clearances i went off of a different set of instructions.
I ended up converting the video to mp4 format and dropped it on my phone, it was a very good reference, and also helped give me the confidence to tackle it.

Also if you drop the transmission, watch for washers, they will be a little thick and between the converter and flywheel.
Very important to ensure you have the converter to pump setback correct or you could break or damage the pump.