Transmission Problems On 4l60e Equipped GMC Truck

Willshire · May 30, 2010

I have a 2007 gmt 900 with the HD trailering pkg does mine have the external tranny cooler? I am pretty sure it does and would anyone have a picture of what it looks like and where its at I cant seem to find it. Or its there and just not looking in the right spot. My 2004 dodge had one I could see it clear as day in the chevy thing are a little tighter. Thanks

Usually in front of a/c condensor should be able to see it behind the grill. That's where mine is

Willshire · May 30, 2010

I know this thread is somewhere on this site but this seems to be a good time to ask. What are the benefits to vette servos and billet 4th servos? Easy to change? A question for the trans guy. During WOT from a stop the 1-2 shift feels like 2 quik shifts, is this normal? 160000miles on it.

ihop · May 31, 2010

I made a new topic earlier this week on this but since your a tranny guy...

I have an 07 Escalade with 73k miles on it. No rims on it, just your run of the mill 18", 31.6 inch tires. I just had a new filter put in for the transmission + the dex 6 that came out from trans pan with the service. It was about 85F today and I was doing some city driving by myself, no load.trailer, my transmission hit 175F-185F. From what I understand from reading is that 200F is dangerzone. Is it too hot at 175-185? I'll be pulling my 5k lbs boat this summer and I dont want to ruin my transmission from overheating. I dont think overheating is covered under PT warranty. Could also these high temps be caused by a mechanical fault, like the pressure solenoid going bad? I don't want to have that replaced when its after my PT warranty.

A bigger rad is a solution but how much would that end up being, I probably wouldnt do it myself since it looks like a pain to get behind the grill in the escalades. Is there anyway besides a bigger rad and tranmission pan to get cooler temps or am I fine the way it is right now?

Thanks, your a great addition to gm trucks forums

Oh yeah, i would think another big reason why the 4l60s failed is because the escalade owners were putting 24's and 26 inch rims on it (not my taste). Thats a hell of a lot of work for the tranny when the stock rim was 17"

Willshire · May 31, 2010

I made a new topic earlier this week on this but since your a tranny guy...

I have an 07 Escalade with 73k miles on it. No rims on it, just your run of the mill 18", 31.6 inch tires. I just had a new filter put in for the transmission + the dex 6 that came out from trans pan with the service. It was about 85F today and I was doing some city driving by myself, no load.trailer, my transmission hit 175F-185F. From what I understand from reading is that 200F is dangerzone. Is it too hot at 175-185? I'll be pulling my 5k lbs boat this summer and I dont want to ruin my transmission from overheating. I dont think overheating is covered under PT warranty. Could also these high temps be caused by a mechanical fault, like the pressure solenoid going bad? I don't want to have that replaced when its after my PT warranty.

A bigger rad is a solution but how much would that end up being, I probably wouldnt do it myself since it looks like a pain to get behind the grill in the escalades. Is there anyway besides a bigger rad and tranmission pan to get cooler temps or am I fine the way it is right now?

Thanks, your a great addition to gm trucks forums

Oh yeah, i would think another big reason why the 4l60s failed is because the escalade owners were putting 24's and 26 inch rims on it (not my taste). Thats a hell of a lot of work for the tranny when the stock rim was 17"

i read many posts on this site that say 175-200 is norm op temp 260 is danger zone. external trans cooler if you need to cool it down. better and less expensive than bigger rad.

Pauldeere · May 31, 2010

Hey Mike. Question: I'm trying to service my 4L60 that in my 2005 Silvy. What's the trick in removing the 2, #40 Torx screws on the Trans. linkage. I got the back screw loose, but the front one is a bitch, it takes a mirror even to see it. Any suggestions?

pistonslap · May 31, 2010

Hey Mike. Question: I'm trying to service my 4L60 that in my 2005 Silvy. What's the trick in removing the 2, #40 Torx screws on the Trans. linkage. I got the back screw loose, but the front one is a bitch, it takes a mirror even to see it. Any suggestions?

Are you trying to remove the pan? I couldn't get the back screw loose on mine either. Also had to use a mirror to see what was in there. I had a socket wrench on it but there was no bloody room to break it loose. If it is like my 2000 i would do like i did and just bend the linkage a bit with a large crescent wrench and then bend it back afterwards. The last thing a person wants to do is strip that screw.

Edit: I meant bend the "mounting bracket" that you were trying to remove.

Edited June 1, 2010 by Rampage1

mikepike1125 · May 31, 2010

My 4l60e went at 48,000 miles on my old 2002 silverado. Thanks GM!!

I have a question.

How does tire size affect the transmission? I had my stock 265 70 r17's on. For the summertime I swap to a 275 55 R20. I did some tire size calculations and it looks like there is not much of a difference between these two tire sets as far as circumference and diameter go. My speedometer reading with 20" wheels on is 1% too slow meaning that when my speedometer reads 60 mph with the 275 55 R20's on I am actually travelling 60.6mph. 638 revolutions per mile for the stock tire vs. 632 revolutions per mile for the non stock tire (275 55 R20). I meant to weigh a tire from each set to see the difference but of course I did not remember this intention until the tires were already on

Anyways, how does this affect the transmission? I have the 6 speed auto.

Edited May 31, 2010 by mikepike1125

jro909 · June 1, 2010

My 4l60e went at 48,000 miles on my old 2002 silverado. Thanks GM!!

I have a question.

How does tire size affect the transmission? I had my stock 265 70 r17's on. For the summertime I swap to a 275 55 R20. I did some tire size calculations and it looks like there is not much of a difference between these two tire sets as far as circumference and diameter go. My speedometer reading with 20" wheels on is 1% too slow meaning that when my speedometer reads 60 mph with the 275 55 R20's on I am actually travelling 60.6mph. 638 revolutions per mile for the stock tire vs. 632 revolutions per mile for the non stock tire (275 55 R20). I meant to weigh a tire from each set to see the difference but of course I did not remember this intention until the tires were already on

Anyways, how does this affect the transmission? I have the 6 speed auto.

changes shift points, unless your geared for it the trans will be shifting alot to try to compensate to apply more force to turn the tires...

mikepike1125 · June 1, 2010

so It will change shift points even though the truck has not been programmed to know it has the larger non stock rim on it?

Does this add extra wear and tear on the tranny? Is it bad for the tranny?

ken1mod · June 3, 2010

Dear Trans Guy,

Nice to have you on this forum.

My question is this, somewhere earlier in this thread you mentioned that the 4l60E often needs rebuild at about 140,000 miles. Question: do they wear out gracefully or does a boney part break?

Ken

Doug_Scott · June 3, 2010

I made a new topic earlier this week on this but since your a tranny guy...

I have an 07 Escalade with 73k miles on it. No rims on it, just your run of the mill 18", 31.6 inch tires. I just had a new filter put in for the transmission + the dex 6 that came out from trans pan with the service. It was about 85F today and I was doing some city driving by myself, no load.trailer, my transmission hit 175F-185F. From what I understand from reading is that 200F is dangerzone. Is it too hot at 175-185? I'll be pulling my 5k lbs boat this summer and I dont want to ruin my transmission from overheating. I dont think overheating is covered under PT warranty. Could also these high temps be caused by a mechanical fault, like the pressure solenoid going bad? I don't want to have that replaced when its after my PT warranty.

A bigger rad is a solution but how much would that end up being, I probably wouldnt do it myself since it looks like a pain to get behind the grill in the escalades. Is there anyway besides a bigger rad and tranmission pan to get cooler temps or am I fine the way it is right now?

Thanks, your a great addition to gm trucks forums

Oh yeah, i would think another big reason why the 4l60s failed is because the escalade owners were putting 24's and 26 inch rims on it (not my taste). Thats a hell of a lot of work for the tranny when the stock rim was 17"

Given that trans fluid uses the engine radiator to cool it (assuming no external cooler), your trans at best will run the same temp as the engine. If the rad is 200 degrees, so is trans fluid. Also remember that engines can and do run at 230 degrees in some situations, so will the trans. The rad cap will increase the boiling point of coolant 4 degrees for every pound of pressure, so a 15 pound rad cap (pretty much the norm) will keep coolant from boiling untill 272 degrees.

Volucris · June 3, 2010

Given that trans fluid uses the engine radiator to cool it (assuming no external cooler), your trans at best will run the same temp as the engine. If the rad is 200 degrees, so is trans fluid. Also remember that engines can and do run at 230 degrees in some situations, so will the trans. The rad cap will increase the boiling point of coolant 4 degrees for every pound of pressure, so a 15 pound rad cap (pretty much the norm) will keep coolant from boiling untill 272 degrees.

That's not true. I don't have an external cooler. Driving down the highway, my trans runs about 80 to 90 degrees hotter than the outside temperature. 100 degree day, my trans is at 185. The engine may be at 210 degrees, but the coolant in the radiator isn't that hot unless the engine is really working. Your thermostat will start to open at 210 degrees, not be wide open at that temp. I monitor my tranny temps with a scanguage II.

smattei14 · June 3, 2010

Sorry guys...not quite sure what trans I have...

I have a 2006 Yukon Denali

I do have a 9x12 stack plate cooler...

And I have ASMOIL in the trans and oil pan.

Thanks!

dlstewart01 · June 3, 2010

Just for you guys info...the guy that started this thread had not been signed on here in a year. But who knows, he may show up at any time...

Doug_Scott · June 3, 2010

Given that trans fluid uses the engine radiator to cool it (assuming no external cooler), your trans at best will run the same temp as the engine. If the rad is 200 degrees, so is trans fluid. Also remember that engines can and do run at 230 degrees in some situations, so will the trans. The rad cap will increase the boiling point of coolant 4 degrees for every pound of pressure, so a 15 pound rad cap (pretty much the norm) will keep coolant from boiling untill 272 degrees.

That's not true. I don't have an external cooler. Driving down the highway, my trans runs about 80 to 90 degrees hotter than the outside temperature. 100 degree day, my trans is at 185. The engine may be at 210 degrees, but the coolant in the radiator isn't that hot unless the engine is really working. Your thermostat will start to open at 210 degrees, not be wide open at that temp. I monitor my tranny temps with a scanguage II.

I think you are confusing the fan switch with the thermostat. When did GM switch from the 195 degree one? The fan may come on at 210 degrees, but the thermostat was opened at 195 degrees.

You are also comparing temps at two different locations. The trans will be the same temp as the rad normally. Normally means that you are not running the torque convertor at stall speed (not locked up, but engine is running faster than the input shaft of transmission). Once the convertor is locked up, very little heat is generated by the trans. Your scangauge is reading the trans temp from the vehicles computer, the same thing that feeds the information to DIC and is exactly as accurate. My point was that there is no way 200 degrees is considerd high for a trans. If you can explain why that is, go for it.