• The site migration is complete! Hopefully everything transferred properly from the multiple decades old software we were using before. If you notice any issues please let me know, thanks! Also, I'm still working on things like chatbox, etc so hopefully those will be working in the next week or two.

Looking for EFFICIENCY upgrades



The reason everyone is giving you a hard time is because it doesn't make financial sense to pull a trans, tear it apart, replace a couple items, then reassemble, and reinstall. 90% of trans cost is labor. In a rebuild TEP replaces all the components that while may be functioning now, are prone to failure. What do you do if you drop $1-2k in a rebuild, and then six months later another hard part fails. Hard parts wear, they fail. You replace them to increase the reliability of the transmission.

None of us are trying to be a^holes but what you are asking doesn't make sound judgement. You either leave it alone, fix the gasket, or rebuild the trans. Why half ass it to save a buck only to have another component failure down the road. There are many common failure points in the transmission. You re-build it to address all of those. Call TEP and ask him to to get you only the parts you need for a budget rebuild.

Wouldn't you be upset if you spent $2k to fix your transmission then 6 months from now a $20 hard part fails because you didn't want to replace it because it was still working at that time.

As far as efficiency goes if there were simple gains to be had GM would have done it.
 
I did initially consider just buying a replacement transmission but it wouldn't be economically feasible.

$1600 + shipping + duty + taxes + ~$2000 --> converted to CAD @ 1.38 = $2760
Labour to install (because I'm completely incapable of doing it myself)... let's say 8 hours mechanic time? - $600

Perhaps my calculations are a bit off but for >$3000 CAD I don't think it's worth it for an oil leak on a car worth about what I just paid for the tranny.

On the other hand my mechanic is willing to do the entire thing, parts and labour for about $2000 and I suspect less if I give him some of the big ticket items. Being a Canadian citizen probably doesn't help, as I suspect it'd be cheaper if I did this in the US but hey, what can I do about that.
 
cnd boooooooooooooooooooooo


your best best is to buy a used tranny and swap it in. be the cheapest route for sure. then just drive it till the rust takes over lol
 
I would look for a salvage yard that has a good trans in stock. my father in law got a used 4T65 for like 700 with shipping, and the mechanic charged 800 for removal and installation. aren't there any salvage yards in Canada?
 


Brettstoner: Your logic is perfectly sound and I agree with you. Fortunately, while lacking specific automotive knowledge relevant to transmissions, I am an automotive engineer and know all about materials so I plan to inspect the parts when the tranny is in pieces at the shop and I can make my own risk assessment as to the condition of the parts they are putting back in. My car is only mildly modded and puts out maybe 200 lbs to the wheels so even without seeing anything I think the risk of hard part failure is low as long as I can control heat soak and torque management in the computer. But again, as you correctly pointed out, if there are any signs or symptoms of impending component failure I will change the parts, whether they help my car go faster or not. My last tranny blew the PCS right after being re-assembled so it had to be done twice. I don't want a repeat of that so your advice is well received.

Have to disagree about GM being efficient though. They apply a pretty liberal safety factor to everything. They also make design decisions that are heavily influenced by durability test requirements. That's why the choked the exhaust off by crushing the downpipe to almost nothing just so they could protect a [useless except for cat health] O2 sensor from some road debris. On top of that, there's all sorts of political red tape, design for manufacturing, design for ergonomics, design for the environment... everybody has their fingers in the decision making process and what you end up with isn't always the most efficient way of doing things from a performance perspective.
 
Last edited:
We do have scrap yards. It didn't occur to me to look there.. I guess because I've never bought anything from one before but if there were a relatively new (low km) tranny in a totalled car (rear end hopefully lol), I might consider it if the price were right.
 
just what shop are you going to that allows you in to inspect the parts and you make the decisions when you just said you lack the knowledge of trannys?

so they are going to stop work, wait for you to show up to have a talk, then get back to work? what world is this that the shop can lay up a lift and stop a man from working?

most places are not that accommodating. nor will they let you stand there and hoover over the guy working on it.
 
J57ltr said:
The truth is you have no idea what you will need to replace until you actually pull it down. You may think the gears are just fine and get in there and they are on their last legs. I was at a friends shop recently and he was rebuilding a transmission and as he pulled one of the clusters out there were chips on the teeth that weren't discovered until actually getting in there.
Click to expand...

That's why I'm going to inspect everything once they've cracked it open. I fully admit the possibility that I'll have to replace some stuff that I would not have otherwise anticipated. I just don't want to gut EVERYTHING when all I'm doing is daily driving this car. The previous owner was this old fart who followed the maintenance schedule religiously and hardly put any miles on the car. I wouldn't be surprised if everything looks mint when it comes out.
 
The last time I had work done they called me and said "Hey your tranny is in pieces on our bench, wanna have a look now?" I said sure, drove over there, had a look and nobody stopped working on anything. I don't plan to hold up the show, just examine the matallurgy of the hard parts and maybe some of the electronics/actuators.

To clarify, I know very little about transmissions.
I know a lot about engineering. Car parts are nothing more than the same basic materials, manufactured using the same conventional manufacturing methods, used in a different application... cars instead of planes or conveyors or elevators. Principles of material science like fatigue, heat treatment, notch hardness, etc, still apply.
 


RRRocketMan said:
That's why I'm going to inspect everything once they've cracked it open. I fully admit the possibility that I'll have to replace some stuff that I would not have otherwise anticipated. I just don't want to gut EVERYTHING when all I'm doing is daily driving this car. The previous owner was this old fart who followed the maintenance schedule religiously and hardly put any miles on the car. I wouldn't be surprised if everything looks mint when it comes out.
Click to expand...

your statements once again are why i keep saying to read a manual. its all coming apart, if its slipping and slam banging gears it needs to be gutted. just so you know, theres got to be 200 parts inside the tranny. you cant leave 1/2 in and work around then even if you wanted to.
 
The transmission isn't slipping or banging into gears. It just has an oil leak :th_scratchhead:

...and they can take everything out of the transmission if they want to, as long as they put it back. I'm not asking them to leave half the components in and try to get at stuff behind them... unless I'm misunderstanding you. The key idea is that they don't replace every component they remove with a new one, if it doesn't need to be replaced AND shouldn't need to be replaced in the near future.
 
then just fix the leak? save tons of money?

pump seals leak, pan gaskets leak. sadly pump seal means its coming out but it dont need to ripped apart to fix that seal. tranny lines leak, aka rust.
 
I honestly don't remember which gasket it was but the mech said it had to come out to fix it... ergo the logic of rebuilding since you're already paying the labour.
 


J57ltr : What do you mean? The L36 is rated at 205 HP and 230 lbs at the flywheel I think right? Since then I've gutted the intake and replaced with a cone filter, added the ZZP HV3 intake runner mod and the ZZP downpipe with U-bend delete. On top of that I've tuned the computer myself. I think that's good for at least another 10 HP/lbs peak and a bunch more at the top end. So let's say I'm at 240 lbs. Factor in 20% drivetrain losses and you're at 200 lbs. I haven't dyno'd the car so this is an estimate but I think it's a fair one.
 
i live on the side of, dont fix whats not broken. if its just a leak, just fix the leak. why add over a grand to the cost of it, like you said why sink almost as much as you paid for into it?

if the fluid is still red to pink, and dont smell burnt, why rebuild it? or take it apart?
 
They told me the leak was unfixable unless I dropped the tranny. I assume this is because there is no access to remove the part of the housing that seals against the leaky gasket in question. If I could have the leak fixed with the tranny in car position, that'd be great.
 
You must log in or register to reply here.
Back
Top