transmission oil change

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Ontheboulder

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time to change the transmission oil and filter, any suggestions??
 

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Be prepared to make a mess and have ATF everywhere.
And don't do it in a windy location or where a lot of dust gets stirred up.

If your pan doesn't have a drain plug in it, do what I do, I find a spot inside where there is no interference with the filter or anything else, drill a hole and weld/braze a nut inside the pan.
Having a drain plug makes the mess possibility reduced a LOT the next time you go to do it.
 

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Pull all of the bolts except one or two on the back side, keep those two loose. Then get the biggest drain pan you have, slip it under and pull the rest of the bolts but the two, then at the front of the pan pry it down slowly and let it drain.

Then you'll want to hold the pan with one hand while removing the last two bolts with the other and carefully lower it.
 

WP29P4A

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Making sure the dog and the cat don't have access to the work area can cut down on surprises and extra unplanned labor. One of the shallow (10 inch) black cement mixing troughs makes a great catch for the trans fluid. It's shallow enough to work over it and wide enough to catch whatever the tranny pan spews, the sloped ends can be helpful too.
 

Matt69olds

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Be prepared to make a mess and have ATF everywhere.
And don't do it in a windy location or where a lot of dust gets stirred up.

If your pan doesn't have a drain plug in it, do what I do, I find a spot inside where there is no interference with the filter or anything else, drill a hole and weld/braze a nut inside the pan.
Having a drain plug makes the mess possibility reduced a LOT the next time you go to do it.


This is the best method for a zero mess (or as close as possible) trans service.

Don’t put the drain plug on the bottom of the pan, if you ever need to remove the trans the drain plug will make it difficult to remove. The trans won’t sit flat on the plywood, not to mention it’s never s good idea having something hang down from the pan.
 

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Since everyone else has given great advice on how to, I'm going to go in a different direction with "any suggestions??"

For a filter I like to use WIX. I've been hooked on them since way back when. And since there are no a plethora of filter tests on the internet WIX is constantly top rated and that has only reinforced that. All my cars, and trucks have them and we use them at the shop as well.

For fluid, I'm very much into factory fill fluid. Which means no universal fluids, and only put in the type the factory did or as close as possible. So at the shop we have an entire shelf of just tranny fluid. In squares I like to use ACDelco ATF Type III (H) part #88865544. If you can't get it at your local parts store, you can order it from amazon. Valvoline still makes a dexIII / Mercon fluid, but I don't like maxlife Valvoline because it's a synthetic, and these trannys did not take synthetic from the factory.

I'm sure others will disagree with me on this, but the above formula has worked out well both in my rigs and customers.
 

AuroraGirl

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Since everyone else has given great advice on how to, I'm going to go in a different direction with "any suggestions??"

For a filter I like to use WIX. I've been hooked on them since way back when. And since there are no a plethora of filter tests on the internet WIX is constantly top rated and that has only reinforced that. All my cars, and trucks have them and we use them at the shop as well.

For fluid, I'm very much into factory fill fluid. Which means no universal fluids, and only put in the type the factory did or as close as possible. So at the shop we have an entire shelf of just tranny fluid. In squares I like to use ACDelco ATF Type III (H) part #88865544. If you can't get it at your local parts store, you can order it from amazon. Valvoline still makes a dexIII / Mercon fluid, but I don't like maxlife Valvoline because it's a synthetic, and these trannys did not take synthetic from the factory.

I'm sure others will disagree with me on this, but the above formula has worked out well both in my rigs and customers.
GM still makes Dex 3 its just not sold under dex 3.

AC Delco Manual Transmission and Transfer Case Fluid, comes in 35 oz jugs if i recall correctly. Its dexron 3 for older manuals/tcases that couldnt use dex vi.
 

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GM still makes Dex 3 its just not sold under dex 3.

AC Delco Manual Transmission and Transfer Case Fluid, comes in 35 oz jugs if i recall correctly. Its dexron 3 for older manuals/tcases that couldnt use dex vi.
Yes, that would be the ACDelco ATF Type III (H) part #88865544, that I mentioned. AFAIK there isn't an actual GM branded dex III.
 

AuroraGirl

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Yes, that would be the ACDelco ATF Type III (H) part #88865544, that I mentioned. AFAIK there isn't an actual GM branded dex III.
Type III is much older spec fluid, im talking about the non synthetic dexron that superseded dex ii in the OP's truck
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That is what Dexron III has been sold as since 2006/7 when Dexron VI replaced III for most uses.

They still make Dex iii becuase Low viscosity, synthetic, and some properties + seal compat just were too different for the non-transmission duties like t cases, manual transmissions, et al.(not ps fluid. dex iii and dex vi should not be used in a gm ps system unless some newer one had a weird need for it. I know they used to say use dex in the ps reservoir but that is old news for many reasons
 

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Type III (H) was the last released version of Dextron III and is NOT synthetic. I think we are saying the same thing. For me I just don't feel good about the idea of dropping in a synthetic fluid into a tranny that has never had it and has a lot of miles. I discussed this in another thread, if mine was a fresh rebuild, I might consider using a new spec'd synthetic fluid, since it has high break down temps, but in the end I probably would stick with ACDelco ATF type III (H) because it has proven to work well in these transmissions. Also as a side note my 1996 Grand Cherokee calls for ATF+3 in the transmission which now completely obsolete so it gets ATF+4, (this is Chrysler fluid not to be confused with the ACDelco stuff). But my transfer case specifies Dextron III, I think that spec is because they did NOT want a synthetic fluid in that transfer case.
 

Ontheboulder

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thanks all for the response. I don't know why they never put a drain in the transmission pans, I will add one before this goes back together. I have heard of people drilling a hole in the pan to drain ,then welding in a drain plug. don't think I want to chance drilling into something inside. definitley will use the non synthetic oil in this thing,since I am not sure of the condition of the trans,other than it works.
 

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thanks all for the response. I don't know why they never put a drain in the transmission pans, I will add one before this goes back together. I have heard of people drilling a hole in the pan to drain ,then welding in a drain plug. don't think I want to chance drilling into something inside. definitley will use the non synthetic oil in this thing,since I am not sure of the condition of the trans,other than it works.
I think the idea was to force you to remove the pan and not skip changing the filter in there. Either that or it was just cheaper to omit it.
 

SirRobyn0

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Type III is much older spec fluid, im talking about the non synthetic dexron that superseded dex ii in the OP's truck
You must be registered for see images attach

That is what Dexron III has been sold as since 2006/7 when Dexron VI replaced III for most uses.

They still make Dex iii becuase Low viscosity, synthetic, and some properties + seal compat just were too different for the non-transmission duties like t cases, manual transmissions, et al.(not ps fluid. dex iii and dex vi should not be used in a gm ps system unless some newer one had a weird need for it. I know they used to say use dex in the ps reservoir but that is old news for many reasons
Ok I just went and checked my reference book for ACDelco fluids. What you have pictured is spec'd as 75W-90 gear oil. Not ATF.

What I was talking about, ACDelco ATF Type III (H) part #88865544, this is an except from the book regarding the fluid I was mentioning.
ACDelco ATF Type III (H) part #88865544 is a premium quality automatic transmission fluid for use in a variety of passenger cars and light trucks. It is formulated with select base oils and additives to meet the heavy demands placed on automatic transmissions, including the generation of electronically controlled transmissions. ACDelco ATF Type III (H) is recommended for the following uses: when DEXRON-III(H), DEXRON-III(G), DEXRON-II(E), DEXRON-II, or Type A Fluids are required, in all automatic transmissions built by GM that do not require DEXRON-VI, and can also be used in some hydraulic and compressor systems where excellent low temperature flow ability is required.
In another section it mentions the base stock which is non-synthetic.

As of 2011 GM will no longer license the word Dextron for older fluids. Many aftermarket fluid manufactures have shortened it to DEX3, because I guess that's ok.

Technically our trucks would have started life with Dextron II (C) released in 73, or Dextron II (D) released in 75, Dextron II (E) released in 1990, Dextron III (H) was released in 2003 and was the last non-synthetic Dextron fluid. Today it is the only non-multi, spec non-synthetic Dextron fluid made, or at least that is available over the counter at parts stores.

To make this more confusing Chrysler had ATF+3, which has is no relation to ACDelco ATF Type III (H) part #88865544, isn't that lovely two name so similar but completely different and incompatible fluids.

If I'm misunderstanding what your saying please correct me.
 

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I think the idea was to force you to remove the pan and not skip changing the filter in there. Either that or it was just cheaper to omit it.
Type III (H) was the last released version of Dextron III and is NOT synthetic. I think we are saying the same thing. For me I just don't feel good about the idea of dropping in a synthetic fluid into a tranny that has never had it and has a lot of miles. I discussed this in another thread, if mine was a fresh rebuild, I might consider using a new spec'd synthetic fluid, since it has high break down temps, but in the end I probably would stick with ACDelco ATF type III (H) because it has proven to work well in these transmissions. Also as a side note my 1996 Grand Cherokee calls for ATF+3 in the transmission which now completely obsolete so it gets ATF+4, (this is Chrysler fluid not to be confused with the ACDelco stuff). But my transfer case specifies Dextron III, I think that spec is because they did NOT want a synthetic fluid in that transfer case.
dexron III isnt synthetic
I wouldnt advise a synthetic for multiple things, only new rebuild with proper seals compatible etc etc. the **** inside the trans that looks like smoking tar that lines all the passages would make one furball kinda thing lol

so I looked at 2 sds of
You must be registered for see images attach

the SAE 75W-85 gear oil* is part of the different way viscosity rating is stated for gear oil purposes, that I can gather.its still dyed red, its not compatible with coppers(fun fact?), the spec it meets is the one for dex 3 (gm spec) GLI 4 if that mattered,

Because you said 75w90 I think you are confusing it with another ac delco fluid which is worded similar but the application is different.

Odour Mild petroleum oil like
.
You must be registered for see images attach

thank god we killed a rabbit with skin contact so we can find out what the amount needed to kill a human would be :893Chainsaw-Smilie-
 

SirRobyn0

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dexron III isnt synthetic
I wouldnt advise a synthetic for multiple things, only new rebuild with proper seals compatible etc etc. the **** inside the trans that looks like smoking tar that lines all the passages would make one furball kinda thing lol

so I looked at 2 sds of
You must be registered for see images attach

the SAE 75W-85 gear oil* is part of the different way viscosity rating is stated for gear oil purposes, that I can gather.its still dyed red, its not compatible with coppers(fun fact?), the spec it meets is the one for dex 3 (gm spec) GLI 4 if that mattered,

Because you said 75w90 I think you are confusing it with another ac delco fluid which is worded similar but the application is different.

Odour Mild petroleum oil like
.
You must be registered for see images attach

thank god we killed a rabbit with skin contact so we can find out what the amount needed to kill a human would be :893Chainsaw-Smilie-
Ok yes I understand what you are saying, and I'm in the opposite corner where I would not recommend a synthetic fluid in a high mileage automatic square transmission. But I do understand your prospective and I think both have merits.

I'm pretty sure I looked up the right part # last night but regardless I cannot recalling having had the 10-4033 in my hand. I'd really love to read the back of the package and see the fluid. It is at local warehouse so I might, if I feel like it order a quart just so I can read the back of the bottle lol.
 

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