i have a 2001 extended cab 3/4 ton with the alison, the truck has 92000 km on it. there are a couple problems
1 in colder weather about 35 F and lower when i put it into reverse it makes a grinding sound or it engages very hard

2 if i reverse up to 10kmh and put in drive it shudders the truck


do i have tranny problems?

? on #2. Do you mean that you are traveling in reverse at 10kmh and you slam it into drive? I don't think that is a good thing to do.http://www.dieselplace.com/forum/images/smilies/eek.gif

if your trans is cold it wll have a firm initial engaugment till it warms up a bit.

Am I following you on question 2?:think: Keep doing that and you will have trans problems.

Also check your fluid and when was the last time you changed the spin on filter on the allison?

Please describe your symptoms of Q 1 and 2 a bit more. grinding is bad.....you mean if the outside temp is under 35 it always does it regardless how warm the truck is ect???

Elaborate a little more on your questions. I hope you're not backing up and then dropping it into Drive. I agree with rat, your tranny won't last long.

k well on #2 my dad has always done this so i thought it was ok so now i know on question 1 it does the grinding more when cold and sometimes hot and i bought the truck used so mabey i should change the spin on. also something i forgot to include that sometimes when stopping at a stop sign it feels as though it lets go of second and drops into neutral. I cant explain it well but while stopping i can feel the resistance of the tranny being in drive and then it seems like it goes into neutral but when i go to get going i am in first gear so i dont know if something is wrong or not

one more thig i have only done the reverse to drive a few times not alot and these other problems were present before i did this

k well on #2 my dad has always done this so i thought it was ok so now i know on question 1 it does the grinding more when cold and sometimes hot and i bought the truck used so mabey i should change the spin on. also something i forgot to include that sometimes when stopping at a stop sign it feels as though it lets go of second and drops into neutral. I cant explain it well but while stopping i can feel the resistance of the tranny being in drive and then it seems like it goes into neutral but when i go to get going i am in first gear so i dont know if something is wrong or not

one more thig i have only done the reverse to drive a few times not alot and these other problems were present before i did this
:eek: :eek: :eek: :eek: why would you do this???:wtf1:

OK, the funy stuff at a stop I believe is deal with 01's and you should be able to get your truck reflashed. Maybe a tech will chime in

On the grinding......maybe its your drainback? Hopefully a tech will chime in on this too???

If your truck has been sitting for awhile try letting it idel for a few minutes before putting it in D and see if this gets rid of your problem.

Change your spin on filter NOW! dont forget about the little magent on the top of the filter.

Dont change from forward to reverse uynless you are at a complete stop.

On Q 1 it just sounds like you torque converter dropping out. If it didn't it would pulse or lunge while idling.

k so i changed the filter and i noticed that it is shifting smoother now but my tranny flud was dark(darker than new tranny fluid.) there was also alot of fines sitting on top of the filter. i dont know if this is because the filter was never changed or there is something wrong. the truck only has 92000k on it and only 30000 wer by me. when ever it does the grind thing it had been warming up for atleast 10 min because it is below 35f. also one more question how much is it for a new clutch kit that would reoplace the old and beef the tranny up


also i now relise how bad the reverse to forward is so quit razzin me

also i now relise how bad the reverse to forward is so quit razzin me

lol.....funny thing is, and I razzed you, when I was 16 I drove my moms minivan and dodge caravan. I blew the tranny and the guy told my mom it was because someone had been doing exactly what you described. guess who that someone was? although i was doing it at a slow roll, no where near 10km/h

and i found out about the clutch kit prics so dont worry about finding that out for me

LCT1000 Transmission M74 Neutral Feel/Flare at Stop - kw accelerate Allison bump clunk decelerate delay engage excessive first flare forward GMT800 hard harsh hesitate intermittent launch loud second #PI00029A - (Apr 12, 2004)
When servicing the vehicle with the VIN you entered, the following diagnosis might be helpful if the vehicle exhibits the described symptoms.
Condition/Concern:
The Allison LCT1000 may experience a "neutral" feeling when coming to a stop. Snapshot data will show that the transmission is being commanded to first gear but turbine speed will not be at 0 rpm (may be at engine speed) with the vehicle stopped (0 output speed). Throttle angle will be a 0%. When throttle is applied, the engine will flare as if the transmission is in neutral and then have a harsh engagement when first gear is achieved. Most likely there will not be any DTCs with this condition. If DTCs are present follow the DTC diagnostic path.
Recommendation/Instructions:
A new calibration has been released to improve the "neutral" feel and shift quality of the 2-1 downshift. The TCM calibration is available on TIS 2000 version 3.50 or later released 3/24/02. The latest ECM calibration should also be installed when the TCM is updated to gain full advantage of the TCM calibration changes. In the event the calibration update does not resolve the concern 2 different causes have been identified for this scenario.
#1: Leakage in the C5 hydraulic clutch circuit. Performing a clutch test should show a slow C5 clutch apply (most easily noticed when performing the 2-1 downshift function of the clutch test). Monitoring pressure in neutral at idle should show pressure below 200 psi. This should also not be intermittent and probably not temperature related. If it is determined from the Clutch Test that the C5 clutch is suspect, repair the C5 clutch.
#2: Valve body concern. This scenario will be hard to duplicate and will likely be temperature related. If the concern appears to be related to a sticking valve the valve body assembly will need to be replaced.

I don't know about the grinding. I had one back on 01 that was grinding like yours but the trannys were still under the exchange program, so it just got a new one. I think I remember there being lots of crap in the pan.

Oh come on I just had to "razz" you one more time about reversing and t hen going into forward. I still don't see how u ever thought this was a good thing lol.

I'm so deliberate when it comes to shifting...I make sure I'm completely stopped, full foot on the brake, shift then off the brake lol. I don't go anywhere without putting the emergency brake on either before shifting into part in order to get the weight of the vehicle off the tranny itself.

If I were to get my trans rebuit even if I were going to keep my truck 100% bone stock I would at a min put new OEM clutches in it with a trans go shift kit and buy an aftermarket single disk converter from SC ATS TTS

Were do you live? it would be well worth it to make a road trip to one of the guys here. Either down to FL and have suncoast do yours, or to Mike in CA or if your in the mid west???

Oh......fluid thats a bit dark is normal and also fuzzies on the magnet are normal. Metal chunks are very bad.

I might be apt to drop the pan and have a looksie.

Change your spin on alli filter every oil change(or every other depending how often you change your oil) I would make sure it gets changed every 10k minimum. I'm ussualy on an 8 k or so scedule.

k i was told the spin on should be changed evry 40000k and for a 50 dollar filter it should last that long as for location i live across from alaska in the yukon so a road trip is out of the question

50$!?!?!?! Some body is screwing ya! Call mike L at 310 674 4440 or go to gmdieseltech.com and get a few of em.

Or I will sell you as many as you want for 35$ shipped:evillol:

:joke: