Guys, I am pulling a code 1870 on my Suburbans OBD and it translates as an irregular performing transmission modulator. Is the transmission modulator the same thing as the shift solenoid? I just want to know when I have it replaced about how much I am going to have to empty my wallet. It actually sounds like something I could do myself.
Well, first of all we would have to know what the year was and what transmission it has. I would guess it's a 4l60E as I have not seen many code P1870's on the 4l80E's. The reason the PCM has set the code is that it has seen the torque converter clutch (TCC) slipping beyond a tolerable range. It is a fairly comon problem on the 4l60E. 95% of the ones I have repaired that set this code need to have the valve body machined to accept a new design TCC valve to solve the problem. About $350 ish in labor and $130 ish in parts. As a GM Master tech for the past 16 years, I can tell you to save yourself some brain damage (and money in the long run) and take it to the dealer for diagnosis and repair... because the valve body repair is ONLY the most likely cause (I can't tell you for sure what is causing the problem without looking at the vehicle). 4 Techinical Service Bulletins exist on this code also, and an independant shop will not have this information available to them. That's why they (independants) will sometimes 'throw parts' at a problem. LP
I had this happen on my 98 S-10 with only 47000 miles. It would shift REALLY hard from 1st to 2nd like it had the mother of all shift kits, but it never triggered the engine light. It happened about 3 or 4 times and never did it again. Some kind of valve sticking in its bore I think. I changed the fluid and filter and have been driving it ever since with no problems.
slipping torque converter clutch Transgo has a simple fix, valve body does need to come off the ******. The valve bore for the PWM is worn out. $350.00 !!! to repair , no way I've done many , many , many of them
You can get the repair done cheeper somewhere other than the dealer, but I wouldn't get it diagnosed anywhere else but the dealer. These repairs will fix most vehicles that have this code, however these are not the only reasons this code will set. Take it to your dealer for diagnosis, then if you want to save a little money, take it somewhere else for the repair. Good luck.. LP
This may or may not help you. My wife has a 96 tahoe and the ****** went out on it so bad that it ate everything including the case in side. Talked to a good friend at the chevy dealer here and found out through him and the TSB's here at my shop that they had a internal grounding problem. So I bought a new trans from Chevy and in the container was a new wirng harness that needed to be spliced into the main harness from the ECU to the trans and a special sticker to wrap the main harness as a retro fit. Did all of that its been perfect ever since.
my 97 blazer set it, then did the tire-barking 1-2 shift as described before. Took it to my trans guy, he did the VB fix. $150. I reset the code and then put motor mounts in it, since the 1-2 shift busted them.
To loudpedal, with all due respect, bulls&%t. Any indie shop that has a copy of Alldata ( or similar) will have access to all TSBs, code translations, troubleshooting charts for ECM codes, etc etc etc. The subscription even gets you quarterly updates. Sorry to hijack...
oh hell, i've got access to alldata here at home, too. ...and who needs alldata when ya got crosley i AIN'T going to go off on "dealers" diagnosing stuff.....
there are a few problems in the 4L60E where the code P1870 can be set..... my experience tells me the worn out bore of PWM is most likely the problem. The TransGo valve cures this in every 4L60E I have installed it. With the TransGo PWM replacement valve the converter clutch comes on quicker with less slipping as designed into it from GM.... this does not set codes since the system still functions within the PCM programed parameters Some independant shops do " throw parts " at a problem becasue the ****** guys are stoopid or never seen the problem. There is such a m***ive aftermarket information system and parts availiblity for any ****** repair , "only" going to the dealer is un-needed. Some folks prefer the dealer , that is fine too. Besides..... I have already placed into snail mail the parts , gaskets and some instructions to El Caballo
[ QUOTE ] Any indie shop that has a copy of Alldata ( or similar) will have access to all TSBs, code translations, troubleshooting charts for ECM codes, etc etc etc. The subscription even gets you quarterly updates. [/ QUOTE ] With all due respect, may I also say bullsh*t. Alldata does not give you, the independent, access to preliminary service information (TSB's that have not yet cleared the legal department), nor does Alldata allow you to talk directly with the people that actually built the vehicle you are working on... ...advantage Dealer. I will agree with you that Alldata is a very useful tool and yes, eventually Alldata does get TSB's and updated diagnostic charts. We also have Alldata at our shop (to work on off-brands that come from the body shop). We mainly use GM service information that is automatically updated daily via satellite. Alldata is consistently 2-3 months behind in updates. Yes, and I know what you are going to say.. "So what, I'll get it eventually". What if the updated info is needed when the vehicle is in the shop now?? You fix it the outdated way, which can lead to a comeback. Armed with my experience, extensive factory training and access to information, with all due respect to everyone here, I'd put my diagnostic skills and friendly advice up against anyone. Everyone is a pro at something, and this is MY forte... Pick your favorite opinion. I get this "the dealer costs too much" or the "my buddy can do that" every time I give advice on the HAMB on a technical topic. Sometimes you CAN get it cheaper and sometimes your buddy CAN fix your problem.. However it is more the exception than the rule in my experience. Sometimes it will cost you less in the long run to just go straight to the Dealer. I see it all the time!! That's why the Dealer's labor rate is higher, they know what they are doing, and if they don't they have the resources to find solutions. That's all I was trying to convey on my first post on this subject. From now on, I think I'll just PM the fellas on here that need help and avoid all the Dealer bashing... Love LP
Had the same problem on my 98 Safari van. Most of the trans guys recommend the transgo kit. In my researching of my problem I found another kit made by Superior. Some of the trans guys told me it was'nt the best kit but it seemed easier to install this kit at home than the other. Easier is not always better but some people seemed to like the kit so I gave it a try.It's been 13 months and 14,000 miles and its working fine. Here is a link to a board where it is discussed. Don't beleive the time frame these guys give you.(I think one guy said it takes 1 1/2 hours). I know nothing about transmissions but with some ***istance from Flt-Blk we got the job done. It took about 5 hours total for a couple of guys that had never been in an automatic transmission. The kit has worked out for me and with a new gasket only sets you back around $60. Here is a link to the discussion. http://www.chevytalk.org/threads/showflat.php?Cat=&Number=547318&page=0&view=collapsed&sb=5&o=&fpart=all&vc=1 If you buy the superior kit, make sure you get the one with boost valve included.
trouble is, around here, the techs rely too much on tsbs andit's pretty easy to do the "shotgun" thing, you know, throw every part that could cause the problem at it and hope one of 'em fixes it. not ALL techs do this but i've worked with a few dealer techs and watched..... ..and the politics of the dealer mentality is something else. been there, done that. btw, we're not any cheaper than dealers..... one more thing, not all dealerships **** and not all indies are hacks.. oh yeah, iatn IS a good deal for the really weird stuff especially.
TSB's are wonderful for the vehicles that are 1-3 yrs old. I have found that I had the TSB info before any one I talked to on the phone at dealers here in Phoenix. I'd give them the TSB number and date..... an hour or 2 later I'd get a call " by golly you are correct on that TSB" With a 1997 vehicle there is a vast amount of high mileage troubles that the dealer techs do not see since a high percentage of vehicles over 5 yrs old never go back to the dealer for repair. There are several good networks for information on the older vehicles. Advantage - dealer? Mayb on new stuff. I had a new 2000 Impala that the dealer could not correct an engine cradle problem that had pops , creaks, rattles that you could feel in the floor when it happened..... GM installed a new cradle when the car had 43k miles on it. A full 7k miles out of warranty At 46k mile the noises returned, I got rid of the car
I'm working on a 1994 Cadillac Deville right now as I type this... I think if the Dealer you work for is a good one, you see the old stuff too. I know I work on a ton of old stuff here. Especially those POS Corvettes We still will get a TSB here and there on the old stuff also. That cradle thing ****s though... We've had a whole bunch of those with no fix yet... LP
Thank you gentlemen, I really appreciate the professional advice and I willaddress the problem appropriately. I do what I can where I can and will gladly leave other stuff to the pros that do it everyday.
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