P1870 code Transmission
 

I know this one has been talked about on here before, but thought I would re-surface it. I have a 99 4WD, auto, 4.3 that has a check engine light on. I get the hard 1-2 shift and a P1870 code.

What is the cheapest fix for this issue? I am being told valve body? Should it be replaced or re-built? Is there another type fluid I should be using? Also, I'm not getting this code in the cold weather, only when its hot.

Any advice would be greatly appreciated.

The P1870 code is kind of a generic code for the tranny, just letting you know something isn't right. My suggestion is to find a reputable shop, have them take a look at it and go from there.

That being said, my dad got this code in his 99 Z71 and ignored it, even with me telling him he needed to take care of it. Well, I borrowed his truck to tow a trailer out to Texas and the tranny ended up going out on me as we got to our destination. I was lucky in that I found a shop that knew the 4L60E inside and out and got the tranny completely rebuilt with beefier parts than stock for pretty much a song.

Next time I'm out that way I'll have my tranny rebuilt by the same shop, though I'll toss in an aftermarket pan with the drain plug in it. I HATE dropping the pan full of oil when changing out the filter.

I've been driving with the P1870 code for 2 years now and only now am I starting to smell burnt tranny fluid. So, I guess it's kicking into touch at last. I can also feel the torque coverter is heading south.

This may be a stupid question but . . .
 

I've got to ask.

I'm looking at replacing my P1870 tranny with a non P1870 unit.

The details: My truck is the '99 model.

The replacement tranny is from a 2002 model. (163,000km) NZ$500 incl torque converter. (Estimate at this stage).

I understand using the search funtion - YES I DID! - that GM had modified the 'sticky valve' issue in 2000 or 2001.

Question: I'm told I can't swap 'cause the computer is not compatible. TRUE or FALSE

Before going ahead, I'll be getting a cost to rebuild the tranny for comparrison purposes.

Let's hear it from you guys, after all you know the trucks better, I think, than anyone in Kiwiland! So your input is crucial to my decision making.

I personally don't believe GM would have made ANY of the mechinical bits different for the overseas market & take the comment above with a pinch of salt BUT, like I said above STUPID????? or not! LOL


Oooops! Sorry for the double post! Was busy watching TV at the same time & I thought I'd started a new thread! Dumbass!!

Had no intention of hijacking this thread.

Ken:
P1870 is just a code that is telling you that the PCM has detected a component slipping inside the transmission. So in effect, you are asking if you can swap a slipping transmission with one that is not slipping. The answer to that question would be a yes any way you look at it.

In terms of compatibility, your transmission should be able to be swapped with any other '98+ 4L60E. I would shoot for a newer transmission though as GM has made improvements to the components inside along the way. I do not believe that you can use a 4L65E or 4L70E without modifications and this may be where your mechanics are getting hung up. The 4L60E was used in a variety of vehicles up to '06 IIRC.

To the OP:
This is not a code to ignore as what can start off as an easily repaired issue can grow into a very expensive and involved repair. There are a few different aftermarket transmission repair kits that are available to cure the P1870 code as it is typically the 1-2 spool valve that leaks past causing a poor 1-2 shift setting this code. There are also rebuilt valve bodies available that can be swapped in if the damage has not already been done.

When I put the shift kit into my Rainier, I will be doing the required rework to the valve body while it is out.

im solving my P1870 code by having the trans rebuilt by AAMCO...dropped my 98 off today because the code was sporadic then a constant so since i refused paying 130 per hr for diagnostic tests from my local GM dealer i decided just to bite the bullet and rebuild the trans...

ITS BS, but at least i know its not my fault, when i bought the truck the trans fluid was really bad(dark as used motor oil) so i changed it out 5qts every 4500ish miles....balljoints were bad too, so previous owners werent as anal on maintaining as i am i guess......


IN SHORT do not ignore that code long or else itll massively mess up your pockets lol

Hey! What you doing here? Didn't you say you were off to the Caymans?

Anyway, thanks for the prompt reply Kyle (as usual). As far as the years go, the latest model imported into New Zealand was the 2002. (1998 - 2002)

Yea, should have had it seen to long way back but because it was not in the 'urgent' catagory & there were, at the time other things going wrong AND, at the time too, I was VERY broke. LOL
From the Extended Warranty side, insurance were wanting it stripped before making a call on wether to fix it or not since it was technically not a "mechanical breakdown" for which I am covered, so if they rejected the claim, I'd have been up the creek without a paddle.

I recently had my valve body redone and the guy installed a kit, basically got rid of the PWM and it is either on or off now for the TC, but it was driven to long with the bad valve and it didnt totally fix my problem, the clutches in the TC are worn now, the valve body repair did help but since the TC is half shot. I am still getting about 180-225 slip, but is indeed better than the 450-525 slip i was getting before.... I am looking into a rebuilt tranny and new TC for $1800, just to pull the tranny and put a new TC in and put tranny back in would cost about $1000 so for another $800 I can have a rebuilt tranny and a warranty.
In your case if you caught the code soon enough you can get the valve body fixed and still be alright, in my case the code was like that before I bought the vehicle and who knows how long driven like that, it will eventually knock the TC out

See TRANSMAN's reply... It sounds like he knows what he's talking about. he talks about it in both these LINKS
http://www.batauto.com/Forums/index.php?topic=4681.0


My Daughters car is throwing the same code. I sucked out a quart of fluid and threw in an additive LUBEGUARD RED .. Didn't help
http://www.batauto.com/Forums/index.php?topic=4013.0

I have seen the pump stator bushing blamed before. This could be dispelled with a pressure check. Not something everyone can do, but it would definitely let you know if you have a problem before the valve body or not.